Picker International, Inc.

Koninklijke Philips Corporation N.v.

Denis W Vanek

G Neil Holland

Douglas M Blakeley

Dean A Putzbach

A magnetic resonance imaging system includes a main magnetic field generator ( ) which produces a temporally constant magnetic field through an examination region ( ). A gradient coil assembly ( ) powered by a gradient field amplifier ( ) produces gradient fields orthogonal to the main magnetic field. The gradient field amplifier ( ) includes a heat sink ( ) for dissipating the thermal energy of at least one power semiconductor device ( ) having a first surface opposite a thermally conductive surface ( ). The thermally conductive surface ( ) is in contact with the heat sink ( ) for transferring the thermal energy. A rigid plate clamp assembly ( ) is affixed to the heat sink ( ) and the semiconductor device ( ) is disposed therebetween. A resiliently deformable spring ( ) is positioned between a first surface of the semiconductor package ( ) and the plate clamp ( ) maintaining positive pressure between the thermally conductive surface ( ) and the heat sink ( ). The resilient deformable spring ( ) has an inner ring ( ) in contact with the rigid plate assembly ( ) and an outer ring ( ) angled from the inner ring in contact with the first surface of the semiconductor package ( ). Preferably, a plurality of semiconductor devices are provided each utilizing a deformable spring to ensure thermal contact between each semiconductor power device and the heat sink.

Apparatus for effecting heat transfer from power semiconductors

A versatile patient support and restraint system is provided. It includes a couch (14) having a top surface (22) for supporting a patient being examined within an examination region (12). Two substantially parallel grooves (20) are formed along a longitudinal direction in the top surface (22) of the couch (14) on opposite sides thereof. Two removable tracks (30) extending in a longitudinal direction are removably seated in the grooves (20). Adjustable restraint straps for securing the patient to the couch (14) are also provided. The adjustable restraint straps include pins attached to opposing ends of the adjustable restraint straps. The pins selectively engage the two removable tracks (30) thereby selectively securing opposing ends of the adjustable restraint straps to opposite sides of the top surface (22) of the couch (14).

Versatile patient restraint system

A support stand (B) adjustably supports either (i) a localized coil assembly or (ii) a portion of a patient within an image region of a magnetic resonance imager (A). A vertical member (42) extends upward from a base (40). A follower (44) is selectively positionable along the vertical member. In one embodiment, a universal joint (48) adjustably mounts a bracket (50) to the follower (FIG. 2). In another embodiment, the follower includes an arm (70) which receives a mounting pin (72) of the supported device. The supported device may be a surface coil (22) or an orthopedic appliance such as a knee support (80) or limb support (90). Every part of the support stand and the supported orthopedic structure, including screws and fasteners are constructed of a material which is invisible in the magnetic resonance images generated by the imager and which is a dielectric to avoid patient shock from induced currents.

Growing community of inventors

Cleveland, OH, United States of America

Denis W Vanek