Method of cancelling lorentz force-produced oscillations in a gradient tube, and magnetic resonance imaging apparatus operating according to the method
    1.
    发明授权
    Method of cancelling lorentz force-produced oscillations in a gradient tube, and magnetic resonance imaging apparatus operating according to the method 失效
    消除梯度管中的力产生振荡的方法,以及根据该方法操作的磁共振成像装置

    公开(公告)号:US06396272B1

    公开(公告)日:2002-05-28

    申请号:US09488719

    申请日:2000-01-20

    IPC分类号: G01V300

    CPC分类号: G01R33/3854

    摘要: In a method for the operation of a magnetic resonance apparatus having at least one gradient coil and elements for generating a force acting on the gradient tube, with which natural oscillation modes of the gradient tube are excited, so as to oppose oscillations of the gradient tube produced by Lorentz forces, drive signals are supplied for the excitation of the elements, and the amplitudes and/or the phases of the drive signals are varied for adjusting the force generated by the elements and acting on the gradient tube so as to compensate modifications of the oscillatory behavior of the gradient tube. The drive signals are varied dependent on at least one measured value representing a criterion for the change of the oscillatory behavior.

    摘要翻译: 在用于操作具有至少一个梯度线圈的磁共振装置的方法和用于产生作用在梯度管上的力的元件的情况下,梯度管的自然振荡模式被激发,从而与梯度管的振荡相对 由洛伦兹力产生的驱动信号被提供用于元件的激励,并且变化驱动信号的振幅和/或相位以调节由元件产生的力并作用在梯度管上,以补偿 梯度管的振荡行为。 驱动信号取决于代表振荡行为变化的标准的至少一个测量值。

    Magnetic resonance apparatus with actuators for counteracting multi-order vibrational modes
    5.
    发明授权
    Magnetic resonance apparatus with actuators for counteracting multi-order vibrational modes 失效
    具有用于抵消多阶振动模式的致动器的磁共振装置

    公开(公告)号:US06353319B1

    公开(公告)日:2002-03-05

    申请号:US09343848

    申请日:1999-06-30

    IPC分类号: G01V300

    CPC分类号: G01R33/3854

    摘要: A magnetic resonance apparatus has a gradient tube at which at least one gradient coil with current flowing therein in operation is arranged, and at which a number of elements for generating a force acting on the gradient tube as needed are arranged, with the positions of the elements being selected dependent at least on the vibratory mode of the gradient tube, so that a counteracting mode is excited given drive of the elements. The elements serving for the excitation of X and/or Y modes are distributed in the middle and around the circumference of the gradient tube with respect to the length of the gradient tube and/or the elements serving for the excitation of the Z mode are distributed along the length and the circumference of the gradient tube.

    摘要翻译: 磁共振装置具有梯度管,在该梯度管上布置有至少一个具有在其中流动的电流的梯度线圈,并且根据需要设置多个用于产生作用在梯度管上的力的元件,其中, 至少根据梯度管的振动模式来选择元件,使得在元件的驱动下激发抵消模式。 用于激发X和/或Y模式的元件相对于梯度管的长度分布在梯度管的中间和周围,并且/或用于Z模式的激发的元件被分布 沿着梯度管的长度和周长。

    Device for repeated semi-invasive abrasion of lesions on the walls of hollow organs
    6.
    发明授权
    Device for repeated semi-invasive abrasion of lesions on the walls of hollow organs 有权
    在中空器官壁上重复半侵入性损伤损伤的装置

    公开(公告)号:US08182499B2

    公开(公告)日:2012-05-22

    申请号:US11064838

    申请日:2005-02-25

    IPC分类号: A61B17/22

    摘要: A device is for repeated semi-invasive abrasion of lesions on the walls of hollow organs, in particular blood vessels or the gastrointestinal tract of a patient. The device includes an outer stent which, fixed in position at the site of the lesions, can be clamped against the wall of the hollow organ and has recesses through which the lesions can inwardly protrude. The device further includes a cutting body which is guided within the outer stent and only negligibly narrows the internal bore of the outer stent, which cutting body has cutting edges sliding on the inner side of the outer stent and is coupled magnetically to an external magnet system via which it can turn about the stent axis and/or can move longitudinally along the stent axis.

    摘要翻译: 一种装置用于在中空器官,特别是血管或患者的胃肠道的壁上重复半侵入性地磨损病变。 该装置包括固定在病变部位的适当位置的外支架,可以被夹紧在中空器官的壁上并具有凹陷,病变可以向内突出。 所述装置还包括切割体,所述切割体在所述外支架内被引导,并且只能使所述外支架的内孔可忽略地变窄,所述切割体具有在所述外支架的内侧上滑动的切割边缘,并且磁耦合到外部磁体系统 通过它可以围绕支架轴线转动和/或可以沿支架轴线纵向移动。