Abstract: A magnetic resonance imaging device including a main magnet, a gradient system with at least one gradient coil, a cryocooler, a thermal bus structure, and an electromagnetic shield arranged between the gradient system and the main magnet. The electromagnetic shield includes spaced shield elements. The electromagnetic shield is configured to provide an electromagnetic shielding of the main magnet from a magnetic field generated by the at least one gradient coil. The thermal bus structure includes thermal bus elements configured to provide a thermal connection between the plurality of spaced shield elements and a cold head of the cryocooler. At least two thermal bus elements of thermal bus elements include different heat transfer properties to provide individualized temperature control of the spaced shield elements.

Abstract: The disclosure relates to a cryogenic system for a magnetic resonance device, comprising a magnet arrangement including at least one superconducting magnet, a first cryocooler thermally connected to the at least one superconducting magnet, a switching device, and a second cryocooler configured to cool a component of the magnet arrangement in dependence of the switching device, wherein the switching device is configured to enable cooling of the component of the magnet arrangement via the second cryocooler when a temperature of the component of the magnet arrangement exceeds a predefined temperature level, and to disable cooling of the component of the magnet arrangement via the second cryocooler when the temperature of the component of the magnet arrangement is below the predefined temperature level. The disclosure further relates to a magnetic resonance device, comprising a cryogenic system.

Abstract: The disclosure relates to a magnetic resonance imaging device comprising a main magnet, a gradient system including at least one gradient coil, a thermal bus structure, a shield structure arranged between the gradient system and the main magnet and a cryocooler including a cold head, wherein the shield structure is configured to reduce a transport of heat energy to the main magnet and wherein the main magnet comprises a magnet spacer configured for spacing individual coils of the main magnet, wherein the thermal bus structure comprises at least one thermal bus element extending through the magnet spacer for providing a thermal connection between the cold head of the cryocooler and the shield structure.

Abstract: A shielding arrangement for a magnetic resonance device, having a main magnet including at least one solenoid coil, a shield structure formed as a double-walled hollow cylinder comprising an outer wall and an inner wall, and a shield tube enclosed between the at least one solenoid coil of the main magnet and the inner wall of the shield structure, wherein the main magnet is arranged between the outer wall and the inner wall of the shield structure, and the shield tube is mechanically supported by the shield structure. The disclosure also relates to a magnetic resonance device having the shielding arrangement.

Abstract: A magnetic resonance imaging device including a main magnet, a gradient system with at least one gradient coil, a cryocooler, a thermal bus structure, and an electromagnetic shield arranged between the gradient system and the main magnet. The electromagnetic shield includes spaced shield elements. The electromagnetic shield is configured to provide an electromagnetic shielding of the main magnet from a magnetic field generated by the at least one gradient coil. The thermal bus structure includes thermal bus elements configured to provide a thermal connection between the plurality of spaced shield elements and a cold head of the cryocooler. At least two thermal bus elements of thermal bus elements include different heat transfer properties to provide individualized temperature control of the spaced shield elements.

Abstract: The disclosure relates to a magnetic resonance imaging device comprising a main magnet, a gradient system including at least one gradient coil, a thermal bus structure, a shield structure arranged between the gradient system and the main magnet and a cryocooler including a cold head, wherein the shield structure is configured to reduce a transport of heat energy to the main magnet and wherein the main magnet comprises a magnet spacer configured for spacing individual coils of the main magnet, wherein the thermal bus structure comprises at least one thermal bus element extending through the magnet spacer for providing a thermal connection between the cold head of the cryocooler and the shield structure.

Abstract: A method for adjusting a magnetic field of a magnetic resonance tomography (MRT)-device having a magnet includes: transferring the magnet from an operating state to a non-operating state in a ramp-down mode; subsequently transferring the magnet from the non-operating state to the operating state in a ramp-up mode; observing a reference parameter different from the magnetic field; setting a target value for the reference parameter; comparing the observed reference parameter to the target value; and finishing the ramp-up mode when the reference parameter reaches the target value.

Abstract: For shimming a background magnetic field of a magnetic resonance imaging apparatus having an outer vacuum chamber (OVC) bore tube, a shimming arrangement has rails on the OVC bore tube and shim trays are mounted between respective rails.

Abstract: In a magnetic resonance apparatus and an operating method therefor, at least one limitation criterion, which describes the avoidance of excessive excitations in an interference spectrum in the magnetic resonance scanner of the apparatus, formed by an interference frequency or an interference frequency range, is specified by a limitation supply processor in order to check a scanning protocol, described by recording parameters, that is to be implemented. At least part of the temporal control sequence of the scanning protocol is determined as a pre-calculation sequence from the recording parameters by a simulation processor and the pre-calculation sequence is checked in a checking processor by the limitation criterion. Implementation of the scanning protocol is prevented when the limitation criterion is not fulfilled.

Abstract: A method for adjusting a magnetic field of a magnetic resonance tomography (MRT)-device having a magnet includes: transferring the magnet from an operating state to a non-operating state in a ramp-down mode; subsequently transferring the magnet from the non-operating state to the operating state in a ramp-up mode; observing a reference parameter different from the magnetic field; setting a target value for the reference parameter; comparing the observed reference parameter to the target value; and finishing the ramp-up mode when the reference parameter reaches the target value.

Abstract: In a method and system for shutting down a superconducting magnet of a magnetic resonance apparatus using a monitoring processor and an energy store, the monitoring processor determines stored energy stored in the energy store at a first point-in-time, and determines a ramp energy required for shutting down, and determines a second point-in-time based on the stored energy and the ramp energy. At the second point-in-time, shutting down of the superconducting magnet is begun.

Abstract: In a method and system for shutting down a superconducting magnet of a magnetic resonance apparatus using a monitoring processor and an energy store, the monitoring processor determines stored energy stored in the energy store at a first point-in-time, and determines a ramp energy required for shutting down, and determines a second point-in-time based on the stored energy and the ramp energy. At the second point-in-time, shutting down of the superconducting magnet is begun.

Abstract: An arrangement for shimming a background magnetic field of a magnetic resonance imaging apparatus having an outer vacuum chamber (OVC) bore tube (1). Rails (8, 9) are provided on the OVC bore tube and shim trays (4) are mounted between respective rails.

Abstract: In a magnetic resonance apparatus and an operating method therefor, at least one limitation criterion, which describes the avoidance of excessive excitations in an interference spectrum in the magnetic resonance scanner of the apparatus, formed by an interference frequency or an interference frequency range, is specified by a limitation supply processor in order to check a scanning protocol, described by recording parameters, that is to be implemented. At least part of the temporal control sequence of the scanning protocol is determined as a pre-calculation sequence from the recording parameters by a simulation processor and the pre-calculation sequence is checked in a checking processor by the limitation criterion. Implementation of the scanning protocol is prevented when the limitation criterion is not fulfilled.