Patent ID: 7996117
Filing Date: 2011-08-09
Classification: G01R,H01F

Abstract:
1. A magnetic resonance imaging apparatus using a super conducting magnet, said magnetic resonance imaging apparatus comprising: a superconducting coil; a container for accommodating the superconducting coil together with refrigerant; a cooling unit for cooling and liquefying gas obtained by vaporizing the refrigerant in the container; a pressure detector for detecting a value of pressure in the container; a heating unit disposed in at least one of the cooling unit and the container; a controller for controlling a heat value of the heating unit and controlling the pressure in the container in accordance with the pressure value detected by the pressure detector; and a judging unit for judging, by using the heat value, whether maintenance of the cooling unit should be performed or not, wherein the controller outputs continuously a current control signal for the heating unit, and the controller determines a period for which maintenance of the cooling unit is required or a period for planning maintenance to be performed, by using a variation rate of the current control signal supplied from the controller to the heating unit, after the current control signal has been substantially constant for a period.