G01R33/3804

Thermal buses for cryogenic applications

A superconducting magnet device including a plurality of superconducting magnet coils; a structural element mechanically and thermally linked to respective magnet coils to retain them in respective relative positions; and a cooling station thermally connected to a cryogenic refrigerator and to the structural element. A thermally conductive path, which passes through the structural element, is established between the cryogenic refrigerator and the superconducting magnet coils through the structural element.

AUTONOMOUS COOLING OF A SUPERCONDUCTIVE DRY-COOLED MR MAGNETIC COIL SYSTEM
20220404445 · 2022-12-22 ·

A method for autonomously cooling down a cryogen-free superconductive magnetic coil system includes: (a1) measuring the current temperature T.sub.actual at the magnet and comparing it to a temperature target value T1.sub.target; (a2) if T.sub.actual>T1.sub.target, actuating a vacuum pump and opening a barrier valve in a vacuum conduit that leads from the vacuum pump into a vacuum vessel containing the magnet; (b1) measuring the current pressure P.sub.actual in the vacuum vessel and comparing it to a pressure target value P1.sub.target; (b2) if P.sub.actual<P1.sub.target, activating a cold head for cooling a cooling arm; (c1) measuring T.sub.actual and comparing it to the first temperature target value T1.sub.target; (c2) if T.sub.actual<T1.sub.target, closing the barrier valve and switching off the vacuum pump; (d1) measuring T.sub.actual and comparing it to a second temperature target value T2.sub.target and maintaining the second temperature target value T2.sub.target.

Systems and methods for magnetic resonance imaging

The present disclosure relates to systems and methods for magnetic resonance imaging (MRI). The systems may include a gradient coil assembly configured to form a gradient magnetic field. The systems may also include a cryostat including a superconducting coil assembly and a magnetic field shielding apparatus arranged on/in a component of the cryostat. The superconducting coil assembly may be configured to form a main magnetic field. The magnetic field shielding apparatus may be configured to shield the superconducting coil assembly from a stray field of the gradient coil assembly. The magnetic field shielding apparatus may include a conductive shielding component, a shielding cylinder, or a combination thereof.

ACCESSIBLE MAGNETIC RESONANCE IMAGING SYSTEM
20220381859 · 2022-12-01 · ·

An ambulance-compatible magnetic resonance imaging (MRI) system for on-site emergency diagnosis includes a mid-field super-conducting head-only magnet including a bore and an active shield arranged relative to the magnet, a passive shield arranged relative to the magnet, the passive shield including a first flange arranged adjacent to a first side of the magnet bore, a second flange arranged adjacent to a second side of the magnet bore, wherein the first flange and the second flange are electrically connected to each other, and wherein the passive shield is operative to capture flux extending out from the magnet bore and return the flux to the magnet. An asymmetric head gradient assembly for generating magnetic gradient field in the mid-field super-conducting magnet is also provided, the magnetic gradient field being between 100-150 mT/m or having a slew rate between 400-800 T/m/s. The MRI system includes a receiver coil and a controller operatively coupled to the receive coil, the controller configured to produce an image based on data obtained from the receive coil. The MRI system is mountable in an ambulance vehicle.

MAGNETIC RESONANCE IMAGING SYSTEM, MAGNETIC RESONANCE IMAGING APPARATUS, COOLING CONTROL DEVICE, AND COOLING CONTROL METHOD

According to one embodiment, a magnetic resonance imaging system includes a first imaging apparatus, a first cooling system, a second imaging apparatus, a second cooling system and a cooling control device. The first imaging apparatus includes a first magnet configured to generate a static magnetic field. The first cooling system is configured to cool the first magnet. The second imaging apparatus includes a second magnet configured to generate a static magnetic field. The second cooling system is configured to cool the second magnet. The cooling control device is configured to switch a cooling target of each of the first cooling system and the second cooling system.

NMR MEASURING ASSEMBLY WITH COLD BORE OF THE CRYOSTAT
20220373625 · 2022-11-24 ·

An NMR measuring arrangement (20) includes a cryostat (1), a superconducting magnet coil system (2) and an NMR probe (3). The cryostat has an evacuated vacuum container (5) and forms a bore (10). A wall (12) of the bore delimits the vacuum container. The cryostat forms only one evacuated gap (13) in a space (18) between the magnet coil system and the wall of the bore. At least a segment of the wall of the bore is thermally coupled to a heat sink of the cryostat. As a result, the NMR measurement arrangement provides more precise NMR measurements (in particular with a higher spectral resolution and/or a higher signal-to-noise ratio) on measurement samples.

Lead and thermal disconnect for ramping of an MRI or other superconducting magnet

A superconducting magnet (10) includes a cryogenic container (22, 32) containing a superconducting magnet winding (20). A sealed electrical feedthrough (36) passes through the cryogenic container. A contactor (40) inside the cryogenic container has an actuator (42) and feedthrough-side and magnet-side electrical terminals (46, 47). A high temperature superconductor (HTS) lead (60) also disposed in the cryogenic container has a first end (62) electrically connected with the magnet-side electrical terminal of the contactor and a second end (64) electrically connected to the superconducting magnet winding. A first stage thermal station (52) thermally connected with the first end of the HTS lead has a temperature (T1) lower than the critical temperature (TC,HTS) of the HTS lead. A second stage thermal station (54) thermally connected with the second end of the HTS lead has a temperature (T2) lower than a critical temperature (TC) of the superconducting magnet winding (20).

THERMAL SHIELD OF MAGNETIC RESONANCE IMAGING MAGNET FOR LIMITING MAGNET GRADIENT INTERACTION

A system for minimizing MGI in a superconducting magnet system of an MRI system includes a thermal shield having bi-metal material. The thermal shield is configured to be disposed about a cold mass of the superconducting magnet system, wherein the bi-metal material is configured to minimize MGI.

QUENCH PROTECTION ARRANGEMENT
20220351888 · 2022-11-03 ·

A quench protection arrangement for a superconducting magnet is disclosed. The arrangement comprises: a superconducting magnet comprising a plurality of magnet sections; a plurality of varistors, wherein each of the plurality of varistors is electrically connected in parallel across a respective one of the plurality of magnet sections; and a heater arrangement electrically connected to the plurality of varistors and configured to apply heat to each of the plurality of magnet sections in response to a change in a voltage across any one or more of the plurality of varistors. A method of protecting a superconducting magnet is also disclosed.

Method for providing setting parameter sets for a magnetic resonance facility, method for operating a magnetic resonance facility, provision facility, magnetic resonance facility and computer program

In a method for providing setting parameter sets for at least one measuring protocol described by protocol parameters for acquiring magnetic resonance data with a magnetic resonance facility, setting parameter set is determined for each of at least two temperature status categories of the magnetic resonance facility using a temperature model describing a development of a temperature status of at least one component of the magnetic resonance facility. The method also includes preventing overheating of the at least one component due to the measurement with the measuring protocol being repeated a maximum number of times for a specified number of repetitions.