Apparatus for moving magnetic objects in a container

Abstract

The device for moving a magnetic object (8) in a container (7) has two pairs of dipoles (1-4) grouped around the container (7). Between the pairs of dipoles (1-4) a pair of quadrupoles (5, 6) is arranged which surround each other concentrically. The dipoles (1-4) and the quadrupoles (5, 6) are formed as Halbach cylinders. This allows the magnetic object (8) to be guided through the container (7) in a particularly efficient manner.

Description

[Technical field]

[0001] The present invention relates to a device for moving magnetic objects in a container, comprising dipoles and quadrupoles grouped around the container, the magnetic fields of the dipoles and the quadrupoles being movable relative to each other.

[0002] Such a device is known, for example, from DE 10 2016 014 192 A1. With this known device, objects can be moved in space. This is done by means of magnetic forces that are adjustable in terms of strength and direction.

[0003] From DE 10 2010022926 A1, a method is known for positioning magnetic nano objects at a target location by means of a gradient magnetic field, which makes it possible to move, for example, instruments for thermal ablation or biopsy needles in the human body.

[0004] From US Patent No. 6,535,092, it is known to arrange individual magnets in a rotatable manner in a ring, thereby forming dipoles and quadrupoles in one structure. However, it is not specified that the magnetic field is generated by the dipoles and quadrupoles together. As a result, only small forces can be introduced into the object with this known device.

[0005] The problem underlying the invention is to improve an apparatus of the type mentioned at the outset, in such a way that a particularly efficient movement of objects within the container is possible.

[0006] This problem is solved according to the invention in that two pairs of dipoles are arranged in different planes spaced apart from each other and two quadrupoles are arranged in a plane between the planes of both dipoles.

[0007] This arrangement allows particularly large forces to be introduced into the object, which can be controlled by suitable positioning of the dipoles and quadrupoles. For example, the object can be held in an intermediate position by the dipoles when the quadrupoles are brought into mutually compensating positions. The generation of the magnetic field and the forces acting on the object is described in detail in DE 10 2016 014 192 A1, to which reference is made for the disclosure. The objects can be of different sizes, preferably paramagnetic or superparamagnetic objects, and can contain, for example, iron oxide. The objects can have diameters in the millimeter range to the nanometer or micrometer range, depending on the field of use.

[0008] According to another advantageous refinement of the invention, the arrangement of the dipoles and quadrupoles in different planes is particularly simple in construction if the magnets for forming the dipoles and quadrupoles are arranged in a Halbach cylinder and surround the space provided for the container, so that the dipoles and quadrupoles arranged in different planes form a cylinder which is preferably arranged one behind the other in the axial direction.

[0009] According to another advantageous refinement of the invention, if two Halbach cylinders, each with magnets for forming a dipole and / or quadrupole, are arranged concentrically with respect to one another, then magnetization or demagnetization of the magnetic field can be achieved simply.

[0010] According to another advantageous refinement of the invention, the strength of the magnetic field can be easily adjusted if the mutually surrounding concentric Halbach cylinders are movable relative to one another.

[0011] According to another advantageous refinement of the invention, if the dipoles and quadrupoles formed as Halbach cylinders each have a drive and are supported so as to be rotatable relative to one another, the dipoles and quadrupoles can be simply driven about in space, by which a resultant magnetic field can be generated in a specific direction and thus a magnetic object can be driven.

[0012] According to another advantageous refinement of the invention, a three-dimensional movement of the object is particularly easily achieved if the carriage for carrying the container containing the object is movable relative to the dipole and quadrupole and the direction of the relative movement of the carriage with respect to the dipole and quadrupole is arranged parallel to the rotation axis of the Halbach cylinder.

[0013] According to another advantageous refinement of the invention, the object driven by the dipoles and quadrupoles can be simply held in the center of the magnetic field if the carriage can run parallel to the rotation axis of the Halbach cylinder, with this arrangement the object always remains in the center of the device, since the counter movement of the carriage makes it possible to compensate for the change in position of the object in the generated magnetic field.

[0014] Advantageously, the device can be used for examining a human or animal body, if the magnetic object is arranged in a probe that is adapted to be introduced into the human or animal body, where the probe can be formed as an endoscope-type capsule for examining the body or can comprise medical instruments for treating the body.

[0015] According to another advantageous refinement of the invention, if the search body has at least one sensor for detecting data, the signal from inside the body can be easily detected. By appropriately arranging an antenna or a memory element, the signal can be selectively stored or transmitted to a receiving device located outside the body.

[0016] The search body can be supplied with current, for example, by an electrical line or a battery. According to another advantageous refinement of the invention, if an induction coil is arranged in the search body, the current for supplying the search body can be generated simply by magnetic induction. This configuration makes batteries or electrical lines unnecessary.

[0017] According to another advantageous refinement of the invention, the device can be constructed particularly simply if the magnetic body is designed as a permanent magnet. Preferably, the magnetic body is designed as a sphere.

[0018] The present invention is susceptible to numerous embodiments, one of which is shown in the drawings and described below in order to more clearly illustrate its basic principles. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 shows an apparatus for moving magnetic objects within a container. [Diagram 2] 2 is a cross-sectional view of the apparatus including the container in the area of ​​the object along line II-II shown in FIG. 1. [Diagram 3] FIG. 2 is an enlarged view of the object shown in FIG. 1 within the search body. [Figure 4] FIG. 2 is a schematic longitudinal section of an arrangement of dipoles and quadrupoles of the device shown in FIG. 1 in a first orientation. [Diagram 5] FIG. 5 is a diagram showing an arrangement of the dipoles and quadrupoles shown in FIG. 4 in a different orientation. [Figure 6] FIG. 2 is a schematic diagram of the geometry of a Halbach cylinder.

[0020] FIG. 1 shows an apparatus with two pairs of dipoles 1-4, which surround one another concentrically, and a pair of quadrupoles 5, 6, which surround one another concentrically, arranged between the pairs of dipoles 1-4. The dipoles 1-4 and the quadrupoles 5, 6 surround a space 18, inside which a container 7, which is illustrated as, for example, a human patient, is located. In the plane of the quadrupoles 5, 6, a magnetic object 8 is located inside the container 7. The dipoles 1-4 and the quadrupoles 5, 6 are each formed as a Halbach cylinder, the length of which is provided for generating a magnetic field in the container 7 to be examined, and each have a tooth arrangement 9 for one drive 10. One of the drives 10 is shown by way of example. By means of this drive, the dipoles 1-4 and the quadrupoles can be rotated around the container. The drive 10 shown has an electric motor 11 with a worm gear 12. In an alternative embodiment, not shown, the electric motor 11 may be engaged with the tooth row 9 via a toothed belt or a gear transmission. The container 7 is located on a carriage 13. This carriage 13 can be run parallel to the axis of the Halbach cylinders of the dipoles 1-4 and the quadrupoles 5,6 by a drive, not shown, so that the object 8 is substantially always located in the center of the Halbach cylinders of the quadrupoles 5,6. At the center, the maximum forces can be transmitted from the dipoles 1-4 and the quadrupoles 5,6 to the object 8.

[0021] Figure 2 shows a cross-sectional view of the device including the vessel 7 along line II-II shown in Figure 1. The movements of the carriage 13, the dipoles 1-4 and the quadrupoles 5, 6 are indicated by arrows in Figures 1 and 2. For example, a magnetic object 8 is placed in an endoscopic searcher 14 and is moved through the vessel 7 by the magnetic fields of the dipoles 1-4 and the quadrupoles 5, 6 and the movement of the carriage 13.

[0022] 3 shows an enlarged view of the object 8 shown in FIGS. 1 and 2, arranged in a search body 14. The object 8 is preferably a spherical permanent magnet or a magnetizable material. The search body 14 further comprises a sensor 15 and an induction coil 16. In an embodiment not shown, the search body 14 may further comprise a medical tool, for example for a biopsy, a thermal treatment or the like.

[0023] In Fig. 4 a longitudinal section of the arrangement of the dipoles 1-4 and the quadrupoles 5, 6 shown in Fig. 1 is shown diagrammatically. The arrows on the dipoles 1-4 and the quadrupoles 5, 6 represent their magnetic orientation. The central arrow labeled F represents the magnetic force resultant vector in the planes x, y, z. The arrow labeled B represents the magnetic flux density. In the shown orientation a magnetic mass 8 is oriented in the x direction and is moved and accelerated by the rotation of both quadrupoles 5, 6 in the central xy plane.

[0024] Figure 5 shows a schematic representation of a different orientation of the dipoles 1-4 and the quadrupoles 5, 6 shown in Figure 1 compared to Figure 4. By corresponding rotation, the two quadrupoles 5, 6 are brought into a mutually compensated position, so that no movement of the object 8 occurs in the xy-plane. The dipoles 1-4 are rotated opposite to one another. This generates a magnetic field gradient along the z-direction and thus causes a movement of the object 8 in this direction.

[0025] In Fig. 6, for the sake of clarity, a schematic diagram of the geometry of a Halbach cylinder is shown. In a) the dipoles 1 to 4 described in Figs. 1 to 5 are shown. A uniform magnetic field is generated by an annular cylinder of permanent magnetic material. The arrows 17 shown on the cylinder 1 indicate the magnetization of the permanent magnetic material, which varies continuously over the entire circumference. However, the arrows 17 may also be formed by individual magnets. The extent (strength) of the magnetic field is shown by the shading of the space 18 surrounded by the cylinder. In this space 18, the container 7 containing the object 8 shown in Figs. 1 to 5 is placed. In a) the magnetic field is uniform. The direction of the magnetic field is shown by the magnetic flux lines 19, with the additional addition of arrows. In b) the quadrupoles 5, 6 shown in Figs. 1 to 5 are shown in the same view as in a). In c) and d) the B of the magnetic field shown in b) is shown. x Ingredients and B y The components are shown, however the black and white arrows indicate the strength and direction of the magnetic field (no field lines). The different strengths of the magnetic field are shown in shading in a / b and c / d.

[0026] Further technical background of the dipoles 1 to 4 and the quadrupoles 5, 6 and the magnetic field gradients generated thereby are described in detail in DE 10 2016 014 192 A1, to which reference is made for the disclosure content.

Claims

1. A device for moving a magnetic object (8) in a container (7), comprising dipoles (1-4) and quadrupoles (5, 6) grouped around the container (7), the magnetic fields of the dipoles (1-4) and the magnetic fields of the quadrupoles (5, 6) being movable relative to each other, 1. A device characterized in that two pairs of dipoles (1-4) are arranged in different planes spaced apart from each other, and two quadrupoles (5, 6) are arranged in a plane between the planes of both dipoles (1-4).

2. 2. The device according to claim 1, wherein the magnets for forming the dipoles (1-4) and the quadrupoles (5, 6) are arranged in a Halbach cylinder, surrounding a space (18) provided for the container (7).

3. 3. The device according to claim 1, wherein two Halbach cylinders each equipped with a magnet for forming the dipoles (1-4) and / or the quadrupoles (5, 6) are arranged concentrically with each other.

4. 3. The apparatus of claim 2, wherein the Halbach cylinders concentrically surrounding each other are movable relative to each other.

5. 3. The device according to claim 2, wherein the dipoles (1-4) and quadrupoles (5, 6) formed as Halbach cylinders each have a drive (10) and are supported so as to be rotatable relative to one another.

6. 5. The device according to claim 4, wherein a carriage (13) for carrying a container (7) containing the object (8) is movable relative to the dipoles (1-4) and the quadrupoles (5, 6), and the direction of the relative movement of the carriage (13) with respect to the dipoles (1-4) and the quadrupoles (5, 6) is arranged parallel to the rotation axis of the Halbach cylinder.

7. 7. The device according to claim 6, characterized in that the carriage (13) is capable of moving parallel to the axis of rotation of the Halbach cylinder.

8. 3. Device according to claim 1 or 2, characterized in that the magnetic object (8) is arranged in a search body (14) adapted to be introduced into the human or animal body.

9. 9. The device according to claim 8, characterized in that the search body (14) comprises at least one sensor (15) for detecting data.

10. 9. The device according to claim 8, characterized in that an induction coil (16) is arranged in the search body (14).

11. 3. The device according to claim 1, wherein the magnetic body (8) is formed as a permanent magnet.

Images