Modular thermal bus for magnetic resonance apparatus

Abstract

The invention relates to a modular thermal bus for a magnetic resonance apparatus. The invention relates to a magnet arrangement (11) for a magnetic resonance apparatus (10), comprising a first magnet coil (31a), a second magnet coil (31b) and a modular thermal bus (30), where the first magnet coil (31a) and the second magnet coil (31b) each comprise superconducting wires (36) arranged in a matrix structure, and where the modular thermal bus (30) comprises embedded elements (32) and link elements (33), where the embedded elements (32) and the link elements (33) are connected to each other. The embedded element (32) is embedded within the matrix structure of the first magnet coil (31a), and wherein the embedded element (32) and the second magnet coil (31b) are thermally and mechanically connected via the link element (33). The invention also relates to a magnetic resonance apparatus (10) for acquiring magnetic resonance data of an object positioned within an imaging region (14) of the magnetic resonance apparatus (10), the magnetic resonance apparatus (10) comprising a magnet arrangement (11) of the invention.

Description

TECHNICAL FIELD

[0001] The present invention relates to a magnet arrangement and a magnetic resonance apparatus. BACKGROUND

[0002] In the past years, the use of conduction-cooled superconducting magnets, also referred to as "dry" magnets, in magnetic resonance apparatuses has significantly increased due to the rising price of helium. While magnetic resonance apparatuses with conduction-cooled superconducting magnets have been commercially available, there is still a large potential for technical improvements. One of the main challenges with conduction-cooled superconducting magnets is the efficient thermal connection between the superconducting magnet and the cryocooler.

[0003] There are several known solutions to address this challenge. In one solution, a closed pipe is attached to the outer circumference of the superconducting magnet. Liquid helium is circulated within the pipe to absorb heat from the superconducting magnet and cool it. A disadvantage of this solution is that the pipe is difficult to manufacture and to install to the superconducting magnet. Furthermore, the pipe constitutes an inherent risk of leakage.

[0004] A further solution involves bonding a highly thermally conductive material to the outer surface of the superconducting magnet to form a thermal bus that transports thermal energy to the cryocooler. While this solution avoids the use of a complex cooling pipe, it provides a low thermal capacity and heat transfer capability, and is therefore typically less efficient in cooling the superconducting magnet. Since the thermal bus is bonded to the outer surface of the superconducting magnet to provide thermal contact and to fix the thermal bus to the superconducting magnet, it is not feasible or even possible to repair and / or replace components of the superconducting magnet. This can be a major disadvantage for magnetic resonance apparatuses with higher magnetic field strengths, such as 3T and 7T, since the material value of the superconducting magnet coils in such apparatuses is significant. SUMMARY

[0005] It is an object of the present invention to provide a conduction-cooled superconducting magnet that improves the cooling efficiency and allows for repair or replacement of components of the superconducting magnet.

[0006] This object is achieved by a magnet arrangement and a magnetic resonance apparatus according to the present invention. Further advantageous embodiments are specified in the dependent claims.

[0007] The magnet arrangement of the present invention is configured for use in a magnetic resonance apparatus. The magnet arrangement comprises a first magnet coil, a second magnet coil and a modular thermal bus.

[0008] The magnet arrangement can comprise or represent a main magnet. It is conceivable that the magnet arrangement comprises a plurality of superconducting coils. In a preferred embodiment, the magnet arrangement comprises at least two solenoid superconducting coils or cylindrical superconducting coils. The at least two solenoid superconducting coils or cylindrical superconducting coils can be rotationally symmetric or comprise a rotationally symmetric body. The first magnet coil and the second magnet coil can represent superconducting coils of the main magnet.

[0009] The at least two superconducting coils of the main magnet may define a common axis. Preferably, the common axis defined by the at least two superconducting coils corresponds to a cylindrical axis and / or an axis of rotational symmetry of the main magnet and / or the magnet arrangement.

[0010] According to an embodiment, the at least two superconducting coils are mechanically coupled and / or mechanically connected. Preferably, the at least two superconducting coils form a cohesive or coherent structure.

[0011] For example, the magnet arrangement may include a magnet support structure configured to provide mechanical support for the at least two superconducting coils. The magnet support structure may be configured to maintain a predetermined spatial arrangement of the at least two superconducting coils. According to an embodiment, the magnet support structure is configured to be mechanically connected to a support structure of the magnetic resonance apparatus, in particular an external vacuum chamber.

[0012] In another example, the at least two superconducting coils may be integrally joined. Preferably, the at least two superconducting coils are integrally joined to at least one spacer disposed between the at least two superconducting coils.

[0013] The magnet assembly may further include a refrigerant vessel and / or a thermal shield. It is contemplated that the magnet assembly is circumferentially enclosed within an outer vacuum chamber of the magnetic resonance apparatus. The vacuum chamber may be formed as a double-walled hollow cylindrical member comprising an outer shell and an inner shell connected by annular end pieces. The magnet assembly may be enclosed between the outer shell and the inner shell of the outer vacuum chamber. The inner shell of the outer vacuum chamber may correspond to a patient bore of the magnetic resonance apparatus containing the magnet assembly.

[0014] The first magnet coil and the second magnet coil each include superconducting wires arranged in a matrix configuration. Preferably, the superconducting wires of the first magnet coil and / or the second magnet coil are wound to form superconducting coils. The matrix configuration of the first magnet coil and / or the second magnet coil may include or contain superconducting wires impregnated with a resin, particularly an epoxy resin. The superconducting wires of the first magnet coil and / or the second magnet coil may be wound to form layers. It is contemplated that the layers of superconducting wire are separated from each other by resin and / or electrical insulators.

[0015] The modular thermal bus includes embedded elements and link elements. The embedded elements and link elements may include or contain thermally conductive materials. In particular, the embedded elements and link elements may include or contain solid thermal conductors, such as metals and / or thermally conductive composite materials. In preferred embodiments, the embedded elements and / or link elements include copper, gold, aluminum, platinum, silver, etc. The embedded elements and / or link elements may be configured as wires, plates, rods, foils, meshes, braids, tubes, etc. The embedded elements and / or link elements may include bends and / or angles.

[0016] The modular thermal bus can be configured to provide thermal and mechanical connections to a cooling system of a magnetic resonance device. In particular, the modular thermal bus elements can be configured to provide thermal and mechanical connections to a cryocooler, a heat exchanger of a cryocooler, a cold head of a cryocooler, and / or a main thermal bus of a magnetic resonance device.

[0017] According to embodiments, the modular thermal bus is in particular configured such that the linking element transfers thermal energy from the embedding element to the cooling system of the magnetic resonance device. The linking element can be configured to bridge a distance between the embedding element and the cooling system of the magnetic resonance device. In particular, the linking element can provide thermal and mechanical connections between the embedding element and the cooling system.

[0018] According to the present application, the embedding element is embedded within a matrix structure of the first magnet coil, and the embedding element and the second magnet coil are thermally and mechanically connected via the linking element.

[0019] The linking element can be thermally and mechanically connected to the embedding element via a force-locking connection, a form-locking connection, and / or a material bond. Preferably, the mechanical connection between the embedding element and the linking element is configured to allow a transfer of thermal energy from the embedding element to the linking element. For example, the linking element can be screwed, bolted, clamped, crimped, and / or glued to the embedding element. In preferred embodiments, the linking element is mechanically connected to the embedding element via a reversible mechanical connection, in particular a screw connection and / or a bolt connection. If a glued joint between the linking element and the embedding element is available and can be separated via the application of heat and / or a solvent, this glued joint can also provide a reversible mechanical connection.

[0020] According to embodiments, the magnet device comprises a further embedding element embedded within a matrix structure of the second magnet coil. The linking element can be mechanically connected to the further embedding element via a force-locking connection, a form-locking connection, and / or a material bond. Preferably, the linking element and the further embedding element are mechanically connected via a reversible mechanical connection.

[0021] In further embodiments, the linking element comprises or includes an attachment device configured to thermally and mechanically connect a portion of the embedding element embedded within the matrix structure of the first magnet coil to a portion of the further embedding element embedded within the matrix structure of the second magnet coil. For example, the linking element can comprise or include a bolt and / or a screw configured to thermally and mechanically connect the embedding element to the further embedding element.

[0022] According to a further embodiment, the embedded elements are embedded within the matrix structure of the first magnet coil and within the matrix structure of the second magnet coil. Of course, the modular thermal bus can comprise embedded elements embedded within the matrix structure of the second magnet coil and within the matrix structure of the third magnet coil. According to the above-mentioned embodiments, the linking elements can be thermally and mechanically connected to one or more embedded elements.

[0023] In yet another further embodiment, the modular thermal bus can comprise a plurality of embedded elements embedded within the matrix structure of the first magnet coil. The modular thermal bus can further comprise a plurality of embedded elements embedded within the matrix structure of the second magnet coil. The embedded elements can be thermally and mechanically connected via one or more linking elements.

[0024] In providing embedded elements embedded within the matrix structure of the first magnet coil, the area of heat transfer between the first magnet coil and the modular thermal bus can be increased compared to conventional thermal bus structures arranged on the outer surface of the main magnet. Thus, the efficiency of transferring thermal energy from the superconducting wire to the cooling system of the magnetic resonance device can be advantageously improved. In particular, a temperature distribution across the matrix structure of the first magnet coil can be advantageously equalized or homogenized.

[0025] As a further advantage, the reversible mechanical connection between the embedded elements and the linking elements can allow for the separation of components or parts of the modular thermal bus. Thus, in case one or more superconducting coils need to be repaired or replaced, the magnet device of the present invention can advantageously be disassembled.

[0026] According to an embodiment of the magnet device of the present invention, the first magnet coil and the second magnet coil are spaced apart from each other.

[0027] For example, the first magnet coil and the second magnet coil can be attached or mounted to a magnet support structure according to the above-mentioned embodiments. The first magnet coil and the second magnet coil can be mechanically connected to the magnet support structure via a force-locking connection, a form-locking connection, and / or a material bond. It is conceivable that the first magnet coil and the second magnet coil are attached to the magnet support structure in such a way that the first magnet coil and the second magnet coil are separated by a gap of a few millimeters or centimeters.

[0028] In a further example, the first magnet coil and the second magnet coil are separated by at least one spacer. The first magnet coil and the second magnet coil can be attached to the at least one spacer via a force-locking connection, a form-locking connection, and / or a material bond. Preferably, the first magnet coil, the second magnet coil, and the at least one spacer form a coherent or cohesive structure.

[0029] When providing link elements and embedded elements according to the present invention, the modular thermal bus can advantageously provide a thermal connection between the first magnet coil and the second magnet coil across the distance between the first magnet coil and the second magnet coil without the need to permanently or irreversibly attach the second magnet coil to the first magnet coil via the modular thermal bus.

[0030] According to a preferred embodiment of the magnet arrangement of the present invention, the first magnet coil and the second magnet coil are spaced apart from each other via at least one spacer arranged between the first magnet coil and the second magnet coil.

[0031] Preferably, the at least one spacer is realized as one or more rings, one or more hollow cylinders, or one or more parts of a ring or a hollow cylinder. It is also conceivable that the at least one spacer is realized as one or more blocks of any suitable shape.

[0032] The at least one spacer may include or contain a thermally conductive material. In particular, the at least one spacer may be configured to transfer thermal energy between the plurality of superconducting coils of the main magnet. Preferably, the at least one spacer comprises an electrically insulating material, an electrically insulating coating, or an electrically insulating layer. For example, the at least one spacer may include or contain a metal, a plastic material, and / or a composite material.

[0033] According to an embodiment, the at least one spacer is configured to fill the gap between the first magnet coil and the second magnet coil. However, the at least one spacer can also be configured to fill the gap between the first magnet coil and the third magnet coil or between the third magnet coil and the second magnet coil.

[0034] The superconducting coils and at least one spacer of the magnet arrangement can form a coherent or cohesive structure. The at least one spacer can be attached to the first magnet coil and / or the second magnet coil via a force-locking connection, a form-locking connection and / or a material connection. Preferably, the at least one spacer is reversibly mounted to the first magnet coil and / or the second magnet coil to allow the magnet arrangement of the present invention to be disassembled. For example, the at least one spacer can be screwed or bolted to the first magnet coil, the second magnet coil and / or the third magnet coil.

[0035] When providing at least one spacer arranged between the first and second magnet coils, an integrally joined magnet arrangement can be provided.Thus, the weight and / or cost associated with a dedicated support cylinder or support structure for the main magnet can be advantageously omitted.

[0036] According to an embodiment of the magnet device of the present invention, the embedding element comprises a connecting portion protruding from the matrix structure of the first magnet coils. The linking element is thermally and mechanically connected to the connecting portion.

[0037] The connection portion can be configured to provide a thermal and mechanical connection to the link element. For example, the connection portion can be configured to be screwed, clamped, bolted and / or glued to the link element. Preferably, the link element and the connection portion are connected via a reversible mechanical connection.

[0038] Depending on the relative spatial orientation of the embedding portion of the embedding element, the connection portion can be angled and / or bent relative to the embedding portion. In particular, the embedding portion can be angled and / or bent such that the connection portion is directed towards an outer surface or a periphery of the first magnet coil. It is also conceivable that the connection portion protruding from the matrix structure of the first magnet coil is angled and / or bent towards an outer peripheral surface of the spacer and / or the magnet support structure.

[0039] According to embodiments, at least a portion of the connection portion is arranged outside of the matrix structure of the first magnet coil, while at least a portion of the embedding element is arranged within the matrix structure of the first magnet coil. Preferably, the portion of the connection portion arranged outside of the matrix structure of the first magnet coil is configured to be thermally and mechanically connected to the link element. For example, the connection portion can comprise a heat transfer region in contact with the link element. The heat transfer region of the connection portion can be configured to transfer an expected heat load generated in the first magnet coil to the link element.

[0040] In providing the connection portion reversibly attached to the link element, the superconducting wires of the first magnet coil can advantageously be thermally connected to the modular thermal bus, while still allowing for a disassembly of the modular thermal bus and / or the magnet arrangement. Furthermore, in leading the connection portion out of the matrix structure of the first magnet coil, the embedding portion of the embedding element can be embedded within the matrix structure of the first magnet coil at any desired depth and / or orientation. Thus, an improved or optimized thermal connection between the first magnet coil and the modular thermal bus can be provided.

[0041] In other embodiments, the embedding element can also extend through a passage or a cavity in at least one spacer or magnet support structure instead of protruding from an outer peripheral surface of the matrix structure of the first magnet coil. For example, the at least one spacer or magnet support structure can comprise a bore, a recess and / or a groove configured for routing the embedding element through the material of the at least one spacer or magnet support structure. Such a passage or cavity can be open and / or accessible from an outer peripheral surface of the magnet arrangement to allow for a disassembly of the modular thermal bus.

[0042] According to embodiments of the magnet arrangement of the present application, the first magnet coil and the at least one spacer comprise a cylindrical shape.

[0043] The magnet arrangement can be cylindrical in shape. In particular, the superconducting coil and the at least one spacer can form a cylindrical body defining a cylindrical axis and / or an axis of rotational symmetry.

[0044] The connecting portion is arranged on an outer peripheral surface of the at least one spacer, and the linking element is mechanically connected to the at least one spacer and the connecting portion at the outer peripheral surface of the at least one spacer.

[0045] The outer peripheral surface of the at least one spacer can form a portion of a lateral surface of the magnet arrangement. It is conceivable that the connecting portion protrudes from the matrix structure of the first magnet coil and is bent or curved over at least a portion of the outer peripheral surface of the at least one spacer. The connecting portion can be in contact with and / or mechanically connected to the at least one spacer. In particular, the connecting portion can be reversibly attached to the outer peripheral surface of the at least one spacer. In a preferred embodiment, the connecting portion and the linking element are reversibly attached to the at least one spacer. For example, the connecting portion and the linking element can be screwed, clamped and / or bolted to the at least one spacer. In a less preferred embodiment, the linking element and / or the connecting portion are connected to the at least one spacer via an adhesive.

[0046] The at least one spacer can advantageously provide a platform or support structure for mechanically fixing the linking element and the connecting portion along the length of the magnet arrangement. Furthermore, in mechanically connecting the connecting portion and the linking element to the at least one spacer, the connection strength and the thermal contact between the linking element and the connecting portion can advantageously be improved. As a further advantage, the at least one spacer can be thermally connected to the modular thermal bus. Thus, the thermal energy transfer from the magnet coil to the modular thermal bus can be further improved.

[0047] In a further embodiment, the magnet arrangement of the present application comprises a thermally conductive element arranged between the embedding element and the linking element.

[0048] In a preferred embodiment, the thermally conductive element is arranged between the linking element and the connecting portion of the embedding element.

[0049] The thermally conductive element can comprise or include a soft material, in particular a soft metal such as indium. However, the thermally conductive element can also comprise or include a thermally conductive adhesive layer and / or a thermally conductive paste layer.

[0050] In arranging the thermally conductive element between the linking element and the embedding element, the thermal energy transfer from the magnet coil to the modular thermal bus can advantageously be improved.

[0051] Furthermore, the thermally conductive element comprising or including a thermally conductive paste and / or a soft metal can facilitate the detachment of the embedding element from the linking element. Thus, maintenance and / or repair services on the magnet arrangement requiring the disassembly of the modular thermal bus can advantageously be simplified.

[0052] In a further embodiment of the magnet arrangement of the present invention, the first magnet coil comprises a cylindrical shape. The portion of the embedding element extending through the matrix structure of the first magnet coil is parallel to a cylindrical axis of the first magnet coil.

[0053] The cylindrical axis of the first magnet coil can correspond to a cylindrical axis and / or a rotational symmetry axis of the magnet arrangement. The portion of the embedding element extending through the matrix structure of the first magnet coil can extend along an axial direction of the first magnet coil and / or of the magnet arrangement.

[0054] Preferably, the portion of the embedding element extending through the matrix structure of the first magnet coil parallel to the cylindrical axis of the first magnet coil portion extends between predetermined layers of superconducting wires of the first magnet coil.

[0055] The portion of the embedding element extending through the matrix structure of the first magnet coil parallel to the cylindrical axis can represent a major portion of the embedding element, for example more than 50%, more than 60%, more than 70%, more than 80% or preferably more than 90% of the embedding element. Due to manufacturing tolerances, the direction of extension of this portion of the embedding element can deviate from the cylindrical axis of the first magnet coil by a few degrees, preferably less than ten degrees, less than five degrees or less than two degrees.

[0056] In a magnetic resonance device, the superconducting wires of a magnet coil are typically layered or stacked in a radial direction. The embedding element of the present invention can advantageously provide a thermal connection between two predetermined layers or windings of the magnet coil and the embedding element. Furthermore, the embedding element extending along an axial direction of the magnet coil can be simply inserted before a new radial layer of superconducting wires is added or wound during the winding process. Thus, the manufacturing process of the magnet coil comprising the embedding element can advantageously be facilitated.

[0057] In a further embodiment of the magnet arrangement according to the present invention, the first magnet coil comprises a cylindrical shape. A portion of the embedding element extends through the matrix structure of the first magnet coil in a radial direction of the first magnet coil.

[0058] The portion of the embedding element extending through the matrix structure of the first magnet coil in the radial direction of the first magnet coil can represent a major portion of the embedding element, for example more than 50%, more than 60%, more than 70%, more than 80% or preferably more than 90% of the embedding element.

[0059] It is conceivable that the portion of the embedding element extending through the matrix structure of the first magnet coil in the radial direction of the first magnet coil extends between predetermined rows of superconducting wires of the first magnet coil. In particular, the portion of the embedding element can extend through the matrix structure of the first magnet coil in a direction that is oriented substantially orthogonally with respect to the cylindrical axis or axis of rotational symmetry of the first magnet coil and / or the magnet device. Due to manufacturing tolerances, the direction of extension of the portion of the embedding element through the matrix structure of the first magnet coil can deviate from the radial direction or transversal plane defined by the first magnet coil and / or the magnet device by a few degrees, preferably less than ten degrees, less than five degrees or less than two degrees.

[0060] The portion of the embedding element protruding from the first magnet coil can represent a connection portion according to the above-described embodiments.

[0061] The embedding element having a portion extending through the matrix structure of the magnet coil in the radial direction can advantageously provide thermal contact with the superconducting wires over a predetermined depth of the superconducting material. However, the manufacturing process of a magnet coil comprising a portion of the embedding element extending through the matrix structure of the magnet coil in the radial direction can be more challenging or more expensive compared to a magnet coil comprising a portion of the embedding element extending between layers of superconducting material in the axial direction of the magnet coil.

[0062] In a preferred embodiment of the magnet device of the present invention, the first magnet coil comprises a cylindrical shape. The extension of the embedding element within the matrix structure of the first magnet coil is limited to a cylindrical sector of the first magnet coil, wherein the cylindrical sector accounts for less than 80%, less than 60%, less than 40% or preferably less than 20% of the circumference of the first magnet coil.

[0063] The first magnet coil can be subdivided into a plurality of imaginary cylindrical sectors. Each of the plurality of cylindrical sectors can define or comprise a portion of the circumference of the first magnet coil.

[0064] The embedding element can form a portion of one or more imaginary cylindrical sectors of the first magnet coil. In particular, the embedding element can extend through one or more imaginary cylindrical sectors. However, the embedding element can be limited to one or more imaginary cylindrical sectors and does not extend into further imaginary cylindrical sectors of the first magnet coil.

[0065] It is conceivable that the one or more imaginary cylindrical sectors comprising the embedding element account for less than 80%, less than 60%, less than 40% or preferably less than 20% of the circumference of the first magnet coil. The extension of the embedding element within the matrix structure of the first magnet coil can be limited to a radial portion of the first magnet coil. The extension of the embedding element within the matrix structure of the first magnet coil can also be limited to a cross-section of the first magnet coil.

[0066] According to embodiments, the extension of the embedded element within the matrix structure of the first magnet coil is limited to a portion of the axial dimension or length of the first magnet coil. For example, the extension of the embedded element within the matrix structure of the first magnet coil can be limited to less than 80%, less than 60% or less than 40% of the axial dimension or length of the first magnet coil.

[0067] When the extension of the embedded element within the matrix structure is limited to a portion of the cylindrical sector or axial dimension of the first magnet coil, it can be advantageous to reduce the costs associated with the manufacturing process of the first magnet coil while still providing a sufficiently large or optimized heat transfer area between the superconducting wire and the embedded element.

[0068] According to embodiments, the magnet device of the present application comprises a plurality of embedded elements embedded within the matrix structure of the first magnet coil and / or the second magnet coil.

[0069] The second magnet coil can be configured in correspondence with the embodiments of the first magnet coil described above. In particular, according to any of the embodiments described herein, one or more embedded elements can be embedded within the matrix structure of the second magnet coil. The matrix structure of the second magnet coil can comprise a resin impregnation layer and / or a winding of superconducting wire. However, it is conceivable that the radial dimension and / or the axial dimension of the second magnet coil differs from the first magnet coil.

[0070] In a preferred embodiment, the first magnet coil comprises a first embedded element embedded within the matrix structure of the first magnet coil and the second magnet coil comprises a second embedded element embedded within the matrix structure of the second magnet coil. The first embedded element and / or the second embedded element can each comprise a portion oriented along a radial direction of the magnet device or oriented parallel to a cylindrical axis of the magnet device.

[0071] According to further embodiments, a plurality of embedded elements can be embedded in the matrix structure of the first magnet coil. The plurality of embedded elements can be arranged at different radial distances from the cylindrical axis of the first magnet coil.

[0072] At least two of the plurality of embedded elements can be embedded at different depths within the matrix structure of the first magnet coil. For example, the first magnet coil can comprise a first embedded element and a second embedded element extending between different layers of superconducting wire along an axial direction of the first magnet coil. In particular, the first embedded element can be arranged at a first radial distance from a cylindrical axis of the first magnet coil, and the second embedded element can be arranged at a second radial distance from the cylindrical axis of the first magnet coil. The first radial distance can be different from the second radial distance. Of course, the first magnet coil can comprise further embedded elements, e.g. a third embedded element and / or a fourth embedded element, arranged at different radial distances from the cylindrical axis of the first magnet coil. The plurality of embedded elements can be embedded within the matrix structure of the second magnet coil in a similar manner.

[0073] According to embodiments, at least two of the plurality of embedded elements can be arranged in different cylindrical sectors of the first magnet coil and / or the second magnet coil. Thus, the embedded elements can advantageously be distributed along a circumferential direction of the magnet arrangement, which can improve the thermal connection with different parts of the magnet arrangement.

[0074] The plurality of embedded elements embedded at different depths within the matrix structure of the magnet coil can advantageously allow different layers of superconducting wire to be thermally connected to the modular thermal bus.

[0075] In a further embodiment, the first magnet coil comprises a first embedded element and a second embedded element extending through the matrix structure of the first magnet coil parallel to a cylindrical axis of the first magnet coil. A radial distance between the first embedded element and the cylindrical axis of the magnet arrangement can correspond to a radial distance between the second embedded element and the cylindrical axis of the magnet arrangement.

[0076] In yet a further embodiment, the plurality of embedded elements can be arranged at different axial portions of the magnet arrangement. For example, the plurality of embedded elements can be arranged at different axial portions of the first magnet coil, the second magnet coil and / or the third magnet coil. In particular, each of the plurality of embedded elements can be arranged at a different axial portion of the magnet arrangement. If the first embedded element and the second embedded element are arranged at different radial distances from a cylindrical axis of the magnet arrangement, the axial portion of the first embedded element can overlap with the axial portion of the second embedded element. It is also conceivable that the first embedded element and the second embedded element are arranged at similar or identical radial distances from the cylindrical axis of the magnet arrangement, axially spaced apart from each other.

[0077] According to the present application, the plurality of embedded elements is thermally and mechanically connected via one or more linking elements.

[0078] For example, in case a plurality of embedded elements is embedded within the first magnet coil, the plurality of embedded elements can be thermally and mechanically connected to a common connection portion. According to any of the embodiments described herein, the common connection portion can be thermally and mechanically connected to one or more link elements and / or to embedded elements embedded within the matrix structure of the second magnet coil. However, each of the plurality of embedded elements can comprise a dedicated or individual connection portion which is thermally and mechanically connected to one or more link elements and / or to embedded elements embedded within the matrix structure of the second magnet coil.

[0079] In a preferred embodiment, the first embedded element is embedded within the matrix structure of the first magnet coil and the second embedded element is embedded within the matrix structure of the second magnet coil. According to any of the embodiments described herein, the connection portion of the first embedded element and the connection portion of the second embedded element can be thermally and mechanically connected to one or more link elements. However, the connection portion of the first embedded element and the connection portion of the second embedded element can also be thermally and mechanically connected to each other via a link element.

[0080] In providing a plurality of embedded elements arranged at different positions within the matrix structure of the magnet coils of the magnet device of the present invention, the heat transfer capability of the modular thermal bus can be advantageously optimized and / or adjusted according to the specific requirements of different magnetic resonance devices, e.g. a whole body scanner or a dedicated scanner for imaging certain body parts.

[0081] According to an embodiment of the magnet device of the present invention, a third magnet coil is arranged between the first magnet coil and the second magnet coil.

[0082] The third magnet coil can comprise one or more embedded elements embedded within the matrix structure of the third magnet coil. The one or more embedded elements of the third magnet coil can be configured according to any of the embodiments of the embedded elements described herein. In particular, the embedded elements of the third magnet coil can be thermally and mechanically connected to a link element.

[0083] The modular thermal bus can comprise a single or coherent link element which is thermally and mechanically connected to the embedded elements of the first magnet coil and the embedded elements of the third magnet coil as well as to the embedded elements of the second magnet coil. However, the modular thermal bus can also comprise a plurality of link elements. For example, the modular thermal bus can comprise at least a first link element and a second link element. The first link element can be thermally and mechanically connected to the embedded elements of the first magnet coil and the embedded elements of the third magnet coil. Likewise, the second link element can be thermally and mechanically connected to the embedded elements of the third magnet coil and the embedded elements of the second magnet coil. Of course, the magnet device of the present invention can comprise further magnet coils, embedded elements and link elements configured according to any of the embodiments described herein.

[0084] The modular hot bus of the magnet arrangement of the present application can advantageously allow a modular adjustment of the number of embedding elements and the number of linking elements based on the specific requirements of the magnetic resonance device. For example, the number of embedding elements and the number of linking elements can be adjusted according to the number of magnet coils of the magnet arrangement of the present application, the depth of the individual magnet coils and / or the axial dimension of the individual magnet coils.

[0085] According to a further embodiment of the magnet arrangement of the present application, the modular hot bus comprises a first embedding element and a second embedding element. The first embedding element is embedded within the first magnet coil and the second embedding element is embedded within the second magnet coil. The first embedding element and the second embedding element are thermally and mechanically connected via the linking element.

[0086] The first embedding element and the second embedding element can be configured according to any of the embodiments described herein.

[0087] For example, according to the above described embodiments, the first magnet coil and the second magnet coil can be spaced apart or separated via at least one spacer. In a preferred embodiment, the first magnet coil and the second magnet coil are mechanically attached to opposite axial ends or axial faces of the spacer and form a coherent structure. It is conceivable that the first magnet coil and the second magnet coil are screwed, bolted and / or glued to the opposite axial ends of the spacer.

[0088] According to an embodiment of the magnet arrangement of the present application, the first embedding element and the second embedding element each comprise a connection portion. The connection portion of the first embedding element and the connection portion of the second embedding element overlap along an axial portion of the magnet arrangement. The linking element is configured to thermally and mechanically connect the connection portion of the first embedding element and the connection portion of the second embedding element.

[0089] For example, the connection portion of the first embedding element and the connection portion of the second embedding element can be bent or curved on an outer peripheral surface of the spacer separating the first magnet coil and the second magnet coil. The connection portion of the first embedding element and the connection portion of the second embedding element can be mechanically attached to the spacer separating the first magnet coil and the second magnet coil. Preferably, the connection portion of the first embedding element and / or the connection portion of the second embedding element are screwed, bolted and / or glued to the outer peripheral surface of the spacer separating the first magnet coil and the second magnet coil.

[0090] The connection portion of the first embedding element and the connection portion of the second embedding element can be thermally and mechanically connected via a linking element. For example, the linking element can represent a rod, a plate, a block or a structure of any shape configured to bridge the gap between the connection portion of the first embedding element and the connection portion of the second embedding element. The linking element can further comprise a support structure for an attachment device configured to mechanically connect the connection portion of the first embedding element to the connection portion of the second embedding element.

[0091] Furthermore, the linking element can comprise an attachment device configured to attach the linking element to the at least one spacer. For example, the linking element can comprise or include one or more bolts and / or screws. The attachment device can also be configured to attach the connection portion of the first embedding element and the connection portion of the second embedding element to the at least one spacer. In a preferred embodiment, the attachment device is configured to provide a thermal and mechanical connection between the connection portion of the first embedding element and the connection portion of the second embedding element. For example, the attachment device can comprise or include one or more screws and / or bolts.

[0092] According to an embodiment, the connection portion of the first embedding element and the connection portion of the second embedding element are configured to overlap on an outer peripheral surface of the at least one spacer. The linking element can comprise or include one or more screws and / or bolts configured to mechanically connect the connection portion of the first embedding element and the connection portion of the second embedding element to the at least one spacer.

[0093] In case the magnet coils of the magnet device are mounted to a dedicated magnet support structure, the linking element can be configured to mechanically connect the connection portion of the first embedding element and the connection portion of the second embedding element to the magnet support structure. The linking element can be configured to thermally and mechanically connect the first embedding element and the second element to each other and also to the magnet support structure. The linking element can be configured according to any of the embodiments described above.

[0094] Preferably, the magnet device, in particular a modular thermal bus, comprises a thermally conductive element according to the embodiments described herein. The thermally conductive element can be configured to increase or improve the thermal energy transfer between the connection portion of the first embedding element and the connection portion of the second embedding element. The thermally conductive element can also be configured to improve the thermal energy transfer between the linking element, the connection portion of the first embedding element and the connection portion of the second embedding element.

[0095] In providing overlapping connection portions of embedding elements which are thermally and mechanically connected via bolts and / or screws, it can be advantageous to reduce the weight and / or material costs associated with the magnet device of the present invention.

[0096] The modular thermal bus according to the present application can advantageously allow for a decoupling of the link elements and thus a dismounting of the magnet arrangement. Furthermore, the modular thermal bus according to the present application can advantageously allow for a thermal and mechanical connection between a plurality of embedded elements and / or link elements of an arbitrary number of magnet coils.

[0097] The first magnet coil and the second magnet coil can represent inner coils or field coils of the magnet arrangement of the present application. The magnet arrangement of the present application can further comprise a plurality of outer coils or shield coils. According to the above-mentioned embodiments, the diameter of the shield coils can exceed the diameter of the first magnet coil and the second magnet coil. According to any of the embodiments described herein, the shield coils can be thermally connected to the modular thermal bus. In particular, one or more embedded elements can be embedded within a matrix structure of such shield coils. The one or more embedded elements can comprise a connection portion thermally and mechanically connected to one or more link elements. The one or more link elements can be thermally and mechanically connected to the modular thermal bus according to the above-mentioned embodiments, to a main thermal bus of the magnetic resonance device and / or to a cooling system.

[0098] The magnetic resonance device of the present application is configured to acquire magnetic resonance data of a subject positioned within an imaging region of the magnetic resonance device. The magnetic resonance device comprises a magnet arrangement according to the above-mentioned embodiments.

[0099] Preferably, the magnetic resonance device is configured to acquire magnetic resonance image data, in particular diagnostic magnetic resonance image data, from the subject positioned within the imaging region. The subject can be an inanimate object or a patient, in particular a human or an animal.

[0100] The magnetic resonance device of the present application can represent a closed-bore scanner. The closed-bore scanner can comprise a substantially cylindrical bore that circumferentially encloses the imaging region. The magnet arrangement of the closed-bore scanner can comprise one or more solenoid superconducting magnet coils that circumferentially surround the imaging region along an axial direction or a rotational symmetry axis of the cylindrical bore. The one or more superconducting magnet coils can comprise superconducting wire having negligible electrical resistance at (or below) a superconducting temperature. The direction of the main magnetic field provided via the one or more superconducting magnet coils can be oriented substantially parallel to a direction of the subject entering the imaging region and / or to the axial direction of the cylindrical bore.

[0101] The magnetic resonance device of the present application can comprise further components required for a proper operation of the magnetic resonance device. For example, the magnetic resonance device can comprise an outer vacuum chamber, a magnet support structure, a thermal shield, a cryocooler, etc. In certain embodiments, the magnetic resonance device comprises a cryogen vessel.

[0102] The cryogen vessel can be configured to store or hold a fluid, in particular a cryogen, at a predetermined temperature level. Preferably, the fluid or cryogen exhibits a low boiling point. Examples of suitable fluids or cryogens are argon, nitrogen, neon, helium, etc. The predetermined temperature level can correspond approximately to the superconducting temperature of the main magnet.

[0103] The cryocooler can be configured to cool and / or maintain one or more superconducting magnet coils of the magnet device at a temperature level close to the superconducting temperature. The magnet device, the thermal shield, the magnet support structure and / or the cryogen vessel can be thermally connected to the cryocooler via a solid heat conductor, a convective loop and / or a heat pipe. In particular, according to the above-described embodiments, one or more superconducting magnet coils of the magnet device can be thermally and mechanically connected to the cryocooler via a modular thermal bus.

[0104] The magnetic resonance apparatus of the present application can represent a "dry" system comprising a minimum of cryogen or no cryogen at all. For example, the magnetic resonance apparatus of the present application can comprise one or more small cryogen vessels thermally connected to the main magnet via a solid heat conductor. The one or more small cryogen vessels can contain a volume of cryogen of less than 10 L, less than 5 L, or less than 1 L. According to embodiments of the magnetic resonance apparatus of the present application, the cryogen vessel is omitted and the magnet device is cooled entirely via thermal conduction.

[0105] In alternative embodiments, the magnetic resonance apparatus of the present application represents a "wet" system. The "wet" system can comprise at least one cryogen vessel comprising a volume of more than 10 L or more than 100 L. The magnet device can be housed within the cryogen vessel and directly cooled by the cryogen.

[0106] The magnetic resonance apparatus shares the advantages of the magnet device of the present application according to the above-described embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0107] Further advantages and details of the present application can be recognized from the embodiments described below and the drawings. In the drawings:

[0108] Figure 1 a schematic diagram of an embodiment of the magnetic resonance apparatus of the present application is shown,

[0109] Figure 2 a schematic diagram of an embodiment of the magnet device of the present application is shown,

[0110] Figure 3 a schematic diagram of an embodiment of the modular thermal bus in the magnet device of the present application is shown,

[0111] Figure 4 a schematic diagram of an embodiment of the modular thermal bus in the magnet device of the present application is shown,

[0112] Figure 5 a schematic diagram illustrating an embodiment of a magnet arrangement of the application,

[0113] Figure 6 a schematic diagram illustrating an embodiment of a magnet arrangement of the application,

[0114] Figure 7 a schematic diagram illustrating an embodiment of a magnet arrangement of the application,

[0115] Figure 8 a schematic diagram illustrating an embodiment of a magnetic resonance apparatus of the application,

[0116] Figure 9 a schematic diagram illustrating an embodiment of a magnet arrangement of the application. DETAILED DESCRIPTION

[0117] Figure 1 An embodiment of a magnetic resonance apparatus 10 according to the application is shown. In the shown example, the magnetic resonance apparatus 10 comprises a static field magnet or main magnet 12 configured to provide a uniform static magnetic field 13 (B0 field) comprising an imaging volume 50. The static magnetic field 13 penetrates an imaging region 14 configured to receive an imaging subject, e.g. a patient 15. The imaging region 14 can correspond to a patient bore configured to accommodate the patient 15 during a magnetic resonance measurement. The imaging region 14 is surrounded in a circumferential direction by the main magnet 12. The main magnet 12 forms part of a magnet arrangement 11 of the application.

[0118] The magnetic resonance apparatus 10 can comprise a patient positioning device 16 configured to transport the patient 15 to the imaging region 14. In particular, the patient positioning device 16 can be configured to transport a body region of the patient 15 of diagnostic interest to the imaging volume 50 or isocenter of the magnetic resonance apparatus 10. The main magnet 12 and other components of the magnetic resonance apparatus 10 can be hidden in a housing.

[0119] The magnetic resonance apparatus 10 can comprise a gradient system comprising one or more gradient coils 18. The one or more gradient coils can be configured to generate gradient magnetic fields in different, preferably orthogonally oriented, spatial directions. The gradient magnetic fields can be used for spatial encoding of magnetic resonance signals or magnetic resonance data acquired during a magnetic resonance measurement. The one or more gradient coils 18 can be activated or controlled via suitable control signals provided by a gradient control unit 19.

[0120] The magnetic resonance device 10 may include an integrated radio frequency antenna 20 (i.e., a body coil). The radio frequency antenna 20 may be activated or controlled via a radio frequency control unit 21. The radio frequency control unit 21 may be configured to control the radio frequency antenna 20 to generate a high-frequency magnetic field and transmit radio frequency excitation pulses to the imaging region 14. The magnetic resonance device 10 may also include a local coil 26. The local coil 26 may be positioned on or near a diagnostically relevant region of the patient 15. The local coil 26 may be configured to transmit radio frequency excitation pulses to the patient 15 and / or receive magnetic resonance signals from the patient 15. It is contemplated that the local coil 26 is controlled via the radio frequency control unit 21.

[0121] Preferably, the magnetic resonance apparatus 10 includes a control unit 22 configured to control the magnetic resonance apparatus 10. The control unit 22 may include a processing unit 28 configured to process magnetic resonance signals and reconstruct magnetic resonance images. The processing unit 28 may also be configured to process input from a user of the magnetic resonance apparatus 10 and / or provide output to the user. To this end, the processing unit 28 and / or the control unit 22 may be connected to a display unit 24 and an input unit 25 via suitable signal connections. In order to prepare for a magnetic resonance measurement, preparation information, such as imaging parameters or patient information, may be provided to the user via the display unit 24. The input unit 25 may be configured to receive information and / or imaging parameters from the user.

[0122] Of course, the magnetic resonance apparatus 10 may include other components and / or functions commonly found in magnetic resonance apparatuses. The general operation of the magnetic resonance apparatus 10 is known to those skilled in the art, and therefore a more detailed description is omitted.

[0123] Figure 2 A schematic diagram of a modular thermal bus 30 of a magnet arrangement 11 of the present invention is shown. In this example, the magnet arrangement 11 includes a plurality of superconducting coils (or magnet coils) 31 that circumferentially enclose an imaging region 14 including an imaging volume 50. The magnet coils 31 are spaced apart by spacers 42 attached to the magnet coils 31 to form a coherent structure. The magnet arrangement 11 has a cylindrical or hollow cylindrical shape. In particular, the magnet arrangement 11 defines a cylindrical axis 41 or an axis of rotational symmetry that intersects the imaging volume 50. The imaging volume 50 provided by the magnet arrangement can be characterized by a magnetic field that is particularly uniform. In particular, the imaging volume 50 can represent the isocenter of the magnetic resonance apparatus 10. The plurality of superconducting coils 31 can represent internal coils or excitation coils of the magnet arrangement 11.

[0124] The modular thermal bus 30 comprises a plurality of embedded elements 32 embedded within a matrix structure of magnet coils 31. Figure 2In the depicted example, the embedded elements 32 are embedded within the matrix structure of each magnet coil 31. The embedded elements 32 include a connection portion 35 that protrudes from the matrix structure of the magnet coil 31 and is bent or curved over an adjacent spacer 42. The connection portions 35 of the embedded elements 32 of two adjacent magnet coils 31 are thermally and mechanically connected via a link element 33. The link element 33 includes attachment means, such as bolts and / or screws, configured to attach the connection portions 35 and the link element 33 to the outer peripheral surface of the spacer 42. Each link element 33 thermally and mechanically connects the connection portions 35 of the embedded elements 32 of adjacent magnet coils 31.

[0125] The link elements 33 can be configured to thermally and mechanically connect the connection portions 35 of a plurality of embedded elements 32. In one embodiment, the link elements 33 form a continuous structure (not shown) attached to the connection portions 35 at each spacer 42. However, the link elements 33 can also include a plurality of disjoint or separate link elements 33. Each of the plurality of disjoint or separate link elements 33 can bridge a gap between two or more spacers 42.

[0126] Preferably, the modular thermal bus 30 is mechanically and thermally attached to a cooling system of the magnetic resonance device 10, for example, the cryocooler 60, the cooling head of the cryocooler 60, the heat exchanger of the cryocooler 60, the cryogen vessel, and / or the main thermal bus 61 (see Figure 8 ).

[0127] Figure 3 A further embodiment of the modular thermal bus 30 of the magnet arrangement 11 of the present application is shown. In the depicted example, a portion of the magnet arrangement 11 including magnet coils 31a and 31b is shown. The magnet coils 31a and 31b are separated by a spacer 42a. Further magnet coils can be attached to a spacer 42b.

[0128] The magnet coil 31a includes superconducting wire 36a wound in such a way as to provide a layer 37 of superconducting wire 36a. In the depicted example, the modular thermal bus 30 includes an embedded element 32a arranged between the outer layer 37i and a second layer 37ii of superconducting wire of the magnet coil 31a. The embedded element 32a includes a connection portion 35a that protrudes from the matrix structure of the magnet coil 31a near the spacer 42a and is bent or curved over the outer peripheral surface of the spacer 42a.

[0129] According to Figure 3In the embodiment shown in FIG. 3, the second embedded element 32b is also arranged between the outer layer 37i of superconducting material of the magnet coil 31b and the second layer 37ii. The connecting portion 35b of the embedded element 32b protrudes from the superconducting material of the magnet coil 31b near the spacer 42b and is bent or folded over the outer peripheral surface of the spacer 42b.

[0130] The linking element 33c provides thermal connection between the magnet coil 31a and the magnet coil 31b by thermal and mechanical connection to the connecting portion 35a of the embedded element 32a and the connecting portion 35b of the embedded element 32b embedded within the matrix structure of the magnet coil 31b. In the example shown, the linking element 33c is formed as a rod or plate configured to bridge the distance between the spacers 42a and 42b. The linking element 33c is attached or mounted to the spacers 42a and 42b via the bolts 33a, 33b, and 33d. The bolts 33a, 33b, and 33d provide thermal and mechanical connection between the linking element 33c, the connecting portion 35a, and the connecting portion 35b.

[0131] Of course, the magnet arrangement 11 can include further magnet coils 31 that are thermally connected via the modular thermal bus according to any of the embodiments described herein.

[0132] Figure 4 A portion of the magnet arrangement 11 of the present invention including the magnet coil 31a and the spacer 42 is shown. Figure 4 The portion of the modular thermal bus 30 depicted in FIG. 3 can be configured according to any of the embodiments described herein. Figure 3 The portion of the modular thermal bus 30 depicted in FIG. 3 can be configured according to any of the embodiments described herein. Figure 3 In comparison to the embodiment shown in FIG. 3, the embedded element 32a is embedded deeper within the matrix structure of the magnet coil 31a. For example, the embedded element 32a is embedded between the third layer 37iii and the fourth layer 37iv of superconducting wire of the magnet coil 31a. Furthermore, the thermally conductive element 34 is arranged between the linking element 33c and the connecting portion 35a of the embedded element 32a.

[0133] The thermally conductive element 34 can include or comprise a thermally conductive glue, a thermally conductive paste, or preferably a soft metal such as indium. The thermally conductive element 34 can be configured to reduce the gap or clearance between the connecting portion 35a and the linking element 33c and / or to increase the thermal transfer area between the connecting portion 35a and the linking element 33c.

[0134] The thermally conductive element 34 can be included in each of the embodiments described herein. Although Figure 4Only a portion of the magnet apparatus 11 of the present invention including the magnet coils 31a, the embedment element 32a, the spacer 42, and a portion of the modular thermal bus 30 is shown, but it should be understood that one or more magnet coils 31 can be mechanically connected or coupled to the spacer 42. According to the embodiments described herein, the one or more magnet coils 31 can be thermally and mechanically connected to the modular thermal bus 30.

[0135] Figure 5 A portion of the magnet arrangement 11 of the present invention comprising a magnet coil 31a and a magnet coil 31b separated by a spacer 42a is depicted. The embedded element 32a may be arranged according to Figure 3 and Figure 4 However, the embedding element 32b includes two connection portions 35b and 35c protruding from the matrix structure of the magnet coils 31b.

[0136] The connecting portions 35b protrude from the matrix structure of the magnet coils 31b near the spacers 42a, while the connecting portions 35c protrude from the matrix structure of the magnet coils 31b near the spacers 42b. In other words, the connecting portions 35b and 35c protrude from the matrix structure of the magnet coils 31b at opposite ends or opposite axial faces of the magnet coils 31b.

[0137] In the depicted example, the linking element 33 includes bolts 33a, 33b and 33c, 33d, which are configured to attach the connecting portions 35a, 35b and 35c, 35d to the respective spacers 42a, 42b. The bolts 33a and 33b provide a thermal and mechanical connection between the connecting portions 35a and 35b, while the bolts 33c and 33d provide a thermal and mechanical connection between the connecting portions 35c and 35d. The connecting portion 35d can represent a connecting portion 35 embedded in another magnet coil 31 (not shown) attached or coupled to the spacer 42b. The embedded element 32 including the connecting portion 35d can be configured as follows: Figure 5 The inlay element 32a or the inlay element 32b shown is configured.

[0138] exist Figure 5 In the example depicted in FIG, heat conducting elements 34a and 34b are arranged between the connecting portions 35a and 35b and between the connecting portions 35d and 35c, respectively.

[0139] The magnet coil 31a may represent an end coil of the magnet arrangement 11 of the present invention. In contrast, the magnet coil 31b may represent a main body coil arranged between the end coil 31a and a further magnet coil 31c (not shown).

[0140] Figure 6Further embodiments of a portion of the magnet arrangement 11 of the application are depicted. In the depicted example, two embedded elements 32a and 32b are embedded in the matrix structure of the magnet coil 31a. The two embedded elements 32a, 32b are embedded in the matrix structure of the magnet coil 31a at different depths or different radial distances from the cylindrical axis 41 of the magnet arrangement 11. For example, the embedded element 32b is arranged closer to the cylindrical axis 41 of the magnet arrangement 11 compared to the embedded element 32a.

[0141] As Figure 6 depicted, the embedded elements 32a and 32b can share a connection portion 35a protruding from the matrix structure of the magnet coil 31a. However, it is also conceivable that the embedded elements 32a and 32b comprise separate connection portions 35 protruding from the superconducting material of the magnet coil 31 at the same location or at different locations. Preferably, the connection portions 35 of the embedded elements 32a and 32b protrude from the matrix structure of the magnet coil 31 in the vicinity of the spacer 42. The connection portions 35 can be bent or folded over the outer peripheral surface of the spacer 42. The link element 33c comprising the bolts 33a and 33b can be configured to attach the connection portions 35 of the embedded elements 32a and 32b to the spacer 42 and to thermally and mechanically connect the embedded elements 32a and 32b to the spacer 42. Figure 6 Further portions of the modular thermal bus 30 and further magnet coils 31 not shown in

[0142] In the depicted embodiment, the embedded elements 32 extend through the matrix structure of the magnet coil 31 parallel to the cylindrical axis 41 or the axis of rotational symmetry of the magnet arrangement 11. Figure 2 to Figure 6 In the depicted embodiment, the embedded elements 32 extend through the matrix structure of the magnet coil 31 parallel to the cylindrical axis 41 or the axis of rotational symmetry of the magnet arrangement 11.

[0143] In some embodiments, the magnet coil 31a can comprise further embedded elements 32 arranged in different cylindrical sectors 61 of the magnet coil 31a. In the depicted example, the cylindrical sector 61a comprises the embedded elements 32a and 32b arranged at different radial distances from the cylindrical axis 41 of the magnet arrangement 11 as shown in Figure 8 In the depicted example, the cylindrical sector 61a comprises the embedded elements 32a and 32b arranged at different radial distances from the cylindrical axis 41 of the magnet arrangement 11 as shown in Figure 6 In the depicted example, the cylindrical sector 61a comprises the embedded elements 32a and 32b arranged at different radial distances from the cylindrical axis 41 of the magnet arrangement 11 as shown in Figure 8 The depicted embodiment of the magnetic resonance apparatus 10 can represent an axial cross-section through the entire magnet coil 31a of the magnet arrangement 11 according to the application. Of course, the magnet coil 31a can comprise further cylindrical sectors 61 comprising embedded elements 32 according to any of the above-described embodiments.

[0144] Figure 7An embodiment of a portion of the magnet arrangement 11 of the present application is shown. In the depicted example, the magnet coil 31a comprises embedded elements 32a and 32b extending through the matrix structure of the magnet coil 31a in a vertical or radial manner. For example, the embedded elements 32a and 32b can extend through the matrix structure of the magnet coil 31a in a direction that is approximately orthogonal to the cylindrical axis 41 of the magnet arrangement 11.

[0145] In contrast to the embodiment depicted in Figure 2 to Figure 6 The embedded elements 32a and 32b extend between columns 38 of superconducting wire, rather than between layers (i.e. rows or ranks) of superconducting wire, in contrast to the embodiment depicted in

[0146] To facilitate manufacture, the embedded elements 32a, 32b can initially be straight or planar pieces. The connecting portions 35a and 35b that protrude from the matrix structure can be bent towards the spacers 42 after the winding process for the magnet coil 31a is complete. Thus, the connecting portions 35a and 35b do not interfere with the winding process.

[0147] In a further embodiment, spacers can be arranged between columns of superconducting wire 36 when winding the magnet coil 31a. The spacers can be removed after the winding process is complete, and the embedded elements 32a and 32b can be inserted into the voids left by the spacers. For example, the embedded elements 32a and 32b can be glued into the voids via a thermally conductive adhesive.

[0148] In yet a further embodiment, the magnet coil 31a can be subdivided into a plurality of individually wound sub-coils that are separated by the embedded elements 32a and 32b. Thus, the embedded elements 32 can advantageously be embedded within the matrix structure of the magnet coil 31a without impeding the winding process. The sub-coils can be electrically connected via conventional superconducting joints.

[0149] Preferably, the embedded elements 32a and 32b comprise separate connecting portions 35a and 35b that protrude from the matrix structure of the magnet coil 31a at different locations. For example, the connecting portions 35a and 35b can protrude from the matrix structure of the magnet coil 31a at the locations where the respective embedded elements 32a, 32b are embedded. However, the embedded elements 32a and 32b can also comprise portions (not shown) that extend between layers of superconducting wire in a direction that is oriented parallel to the cylindrical axis 41 of the magnet arrangement 11.

[0150] In Figure 7, the linking element 33c includes bolts 33a and 33b configured to attach the connecting portions 35a and 35b to the outer peripheral surface of the spacer 42. The linking element 33c thermally and mechanically connects the connecting portions 35a and 35b to each other and also to another portion of the modular thermal bus 30.

[0151] The embedding elements 32a and 32b may penetrate to different depths into the matrix structure of the magnet coils 31. For example, the embedding elements 32a and 32b may have different extensions through the matrix structure of the first magnet coils 31a in the radial direction.

[0152] According to an alternative embodiment, the embedding elements 32a and 32b share a single connection portion 35 at one location that protrudes from the matrix structure of the magnet coils 31a.

[0153] Figure 8 A cross-sectional view of an embodiment of a magnetic resonance apparatus 10 according to the invention is shown, for example through Figure 6 , an axial cross-section of the magnet coil 31a is depicted in FIG. The magnetic resonance apparatus 10 includes an outer vacuum chamber 42 that provides an outer enclosure for the magnet arrangement 11. Specifically, the outer vacuum chamber 42 separates a surrounding environment 70 from a vacuum region 71 enclosed by the outer vacuum chamber 42. The outer vacuum chamber 42 may represent a double-walled hollow cylindrical member comprising an outer shell and an inner shell. The inner shell of the outer vacuum chamber 42 may represent a patient bore that circumferentially encloses the imaging region 14.

[0154] The magnetic resonance apparatus 10 may further include a heat shield (not shown). The heat shield may also be implemented as a double-walled hollow cylindrical member having an outer wall, an inner wall, and an end wall connecting the outer wall and the inner wall. The outer wall and the inner wall of the heat shield may circumferentially surround the magnet arrangement 11 including the magnet coil 31a.

[0155] In the depicted example, the magnetic resonance apparatus 10 of the present invention includes a cryocooler 60 mounted on the outer vacuum chamber 42. The cryocooler 60 is configured to cool the magnet arrangement 11 and also any thermal shields, further thermal shields, magnet support structures and / or cryogen vessels of the magnetic resonance apparatus 10.

[0156] The cryocooler 60 typically includes a compressor (not shown) that supplies pressurized gas to the cryocooler 60. The cryocooler 60 may also include a cooling head comprising one or more cooling stages. In a preferred embodiment, a first cooling stage 60a of the cooling head is thermally connected to a thermal shield (not shown), while a second cooling stage 60b of the cooling head is thermally connected to the magnet coil 31a via a main thermal bus 61 connected to the modular thermal bus 30. In one example, the first cooling stage 60a provides a temperature level of approximately 50K, while the second cooling stage 60b provides a temperature level of approximately 4K.

[0157] In a "dry" magnetic resonance device, the cooling stages 60a and 60b of the cryocooler 60 can be connected to the magnet device 11 via solid thermal conductors 61. However, the magnetic resonance device 10 can also comprise one or more small refrigerant vessels or thermal buffers (not shown) which are thermally connected to the cryocooler 60 and / or the magnet device 11 via solid thermal conductors, heat pipes and / or convection loops. In particular, the one or more refrigerant vessels or thermal buffers can be thermally connected to the magnet device 11 via the modular thermal bus 30.

[0158] In the embodiment shown in Figure 8 In the embodiment shown in Figure 6 The embedded elements 32a and 32b shown in are arranged at different radial distances from the cylindrical axis 41 of the magnet device 11. The cylindrical sector 61b comprises further embedded elements 32d which extend through the matrix structure of the first magnet coil 31a parallel to the cylindrical axis 41 of the first magnet coil 31a.

[0159] The modular thermal bus 30 further comprises an embedded element 32c which extends in radial direction through the matrix structure of the magnet coil 31a. Since the cylindrical sector defined by the embedded element 32c is insignificant compared to the cylindrical sectors 61a and 61b, it can be neglected.

[0160] In the above embodiments, the superconducting coils 31, i.e. the magnet coils, can be serially joined via spacers 42 and the embedded elements 32 of the modular thermal bus 30 can be embedded within the matrix structure of said superconducting coils 31. The embedded elements 32 can be thermally and mechanically connected to the linking elements 33 of the modular thermal bus 30 which are configured to thermally connect the superconducting coils 31 to a heat exchanger, a refrigerant vessel and / or a main thermal bus 61 (see Figure 8 ) of a cooling system, e.g. a cryocooler 60. Preferably, a thermally conductive element 34 is arranged between the linking element 33 and the connection portion 35 of the embedded element 32 to improve the thermal contact.

[0161] The magnet device 11 according to the present application can comprise one or more modular thermal buses 30 which are distributed at regular or irregular intervals around the circumference of the magnet coils 31 of the magnet device 11.

[0162] For example, Figure 9 An embodiment of the magnet device 11 of the present application is shown comprising two modular heat buses 30a and 30b arranged at opposite sides of the magnet device 11. In the depicted example, the modular heat buses 30a and 30b are identically configured, and therefore, the labeling of the elements of the modular heat bus 30b has been omitted. However, each modular heat bus 30a, 30b can be configured according to any of the embodiments described herein.

[0163] In providing a plurality of modular heat buses 30 distributed over the circumference of the magnet device 11, the heat transfer capacity between the magnet coils 31 and the cooling system of the magnetic resonance device can advantageously be increased or improved. Furthermore, the plurality of modular heat buses 30 can advantageously equalize the heat distribution in the circumferential direction of the magnet device 11.

[0164] In the depicted example, the linking element 33 is shaped such that the hand of a tool and / or a technician is arranged between the outer peripheral surface of the magnet coil 31 and the linking element 33. In particular, the portion of the linking element 33 bridging the space between two adjacent spacers 42 is raised, angled and / or bent such that a predetermined gap is provided between the outer peripheral surface of the magnet coil 31 and the linking element 33.

[0165] In providing a linking element 33 with a raised portion, the assembly or disassembly of the modular heat bus 30 can advantageously be facilitated.

[0166] The embodiments described herein are to be considered as examples. It is understood that the individual embodiments can be extended by or in combination with features of other embodiments, if not stated otherwise. Figure 1 to Figure 9 The embodiments depicted herein are drawings which are not necessarily drawn to scale.

[0167] Independent of the grammatical term usage, an individual with a male identity or a female identity is included within the term.

Claims

1. A magnet arrangement (11) for a magnetic resonance apparatus (10), comprising: A first magnet coil (31a), a second magnet coil (31b) and a modular thermal bus (30), wherein the first magnet coil (31a) and the second magnet coil (31b) each include a superconducting wire (36) arranged in a matrix structure, and wherein the modular thermal bus (30) includes an embedded element (32) and a linking element (33), wherein the embedded element (32) is embedded in the matrix structure of the first magnet coil (31a), and wherein the embedded element (32) and the second magnet coil (31b) are thermally and mechanically connected via the linking element (33).

2. The magnet arrangement (11) according to claim 1, wherein The first magnet coil (31a) and the second magnet coil (31b) are spaced apart from each other.

3. The magnet arrangement (11) according to claim 2, wherein The first magnet coil (31a) and the second magnet coil (31b) are spaced apart via at least one spacer (42) disposed between the first magnet coil (31a) and the second magnet coil (31b).

4. The magnet arrangement (11) according to one of the preceding claims, wherein The embedding element (32) includes a connection portion (35) protruding from the matrix structure of the first magnet coil (31a), and wherein the linking element (33) is thermally and mechanically connected to the connection portion (35).

5. The magnet arrangement (11) according to claim 3 and 4, wherein The first magnet coil (31a) and the at least one spacer (42) include a cylindrical shape, wherein the connecting portion (35) is arranged on the outer peripheral surface of the at least one spacer (42), and wherein the linking element (33) is mechanically connected to the at least one spacer (42) and the connecting portion (35) at the outer peripheral surface of the at least one spacer (42).

6. The magnet arrangement (11) according to claim 4 or 5, wherein: The first magnet coil (31a) comprises a cylindrical shape, and wherein the embedding element (32) comprises two connecting portions (35) protruding from the matrix structure of the first magnet coil (31a) at opposite axial ends of the first magnet coil (31a).

7. The magnet arrangement (11) according to one of the preceding claims, comprising a heat conducting element (34) arranged between the embedding element (32) and the linking element (33).

8. The magnet arrangement (11) according to one of the preceding claims, wherein The first magnet coil (31a) comprises a cylindrical shape, and wherein a portion of the embedding element (32) extends through the matrix structure of the first magnet coil (31a) parallel to the cylindrical axis (41) of the first magnet coil (31a).

9. The magnet arrangement (11) according to one of the preceding claims, wherein The first magnet coil (31a) includes a cylindrical shape, and wherein a portion of the embedding element (32) extends through the matrix structure of the first magnet coil (31a) in a radial direction of the first magnet coil (31a).

10. The magnet arrangement (11) according to one of the preceding claims, wherein The first magnet coil (31a) comprises a cylindrical shape, and wherein the extension of the embedded element (32) within the matrix structure of the first magnet coil (31a) is limited to a cylindrical sector (61) of the first magnet coil (31a), wherein the cylindrical sector (61) occupies less than 80%, less than 60%, less than 40% or preferably less than 20% of the circumference of the first magnet coil (31a).

11. The magnet arrangement (11) according to one of the preceding claims, comprising a plurality of embedded elements (32) embedded in a matrix structure of the first magnet coil (31a) and / or the second magnet coil (31b), wherein: The plurality of embedded elements (32) are thermally and mechanically connected via one or more linking elements (33).

12. The magnet arrangement (11) according to claim 11, wherein At least two embedding elements (32) among the plurality of embedding elements (32) are embedded at different depths within the matrix structure of the first magnetic coil (31a).

13. The magnet arrangement (11) according to one of the preceding claims, wherein The third magnet coil is arranged between the first magnet coil (31a) and the second magnet coil (31b).

14. The magnet arrangement (11) according to one of the preceding claims, wherein The modular thermal bus (30) includes a first embedded element (32a) and a second embedded element (32b), wherein the first embedded element (32a) is embedded in the first magnet coil (31a), and the second embedded element (32b) is embedded in the second magnet coil (31b), wherein the first embedded element (32a) and the second embedded element (32b) are thermally and mechanically connected via the linking element (33).

15. The magnet arrangement (11) according to claim 14, wherein The first embedment element (32a) and the second embedment element (32b) each include a connecting portion (35a; 35b), wherein the connecting portions (35a; 35b) of the first embedment element (32a) and the second embedment element (32b) overlap along an axial portion of the magnet arrangement (11), and wherein the linking element (33) is configured to thermally and mechanically connect the connecting portions (35a; 35b) of the first embedment element (32a) and the second embedment element (32b).

16. A magnetic resonance apparatus (10) for acquiring magnetic resonance data of an object positioned in an imaging region (14) of the magnetic resonance apparatus (10), the magnetic resonance apparatus (10) comprising a magnet arrangement (11) according to one of the preceding claims.

Images