Abstract: A mandrel for holding gradient coils in an instrument that measures nuclear magnetic resonance is fastened directly to the magnet of this instrument. It is shown that this arrangement can be used to reduce the output of noise while, at the same time, making it easy to adjust the position of the mandrel. The device comprises two sets of brackets fastened by their struts, on either side of the magnet, to the end rings of the magnet. Each bracket exerts a holding force on the mandrel.

Abstract: A gradient coil is provided for a nuclear magnetic resonance image forming apparatus, the gradient coil being formed of four identical arrangements symmetrical with respect to the centre of a predetermined examination space. These arrangements comprise conductors formed in the shape of a saddle. In a particular embodiment for each arrangement two groups of conductors are provided. They may moreover be superimposed. In the invention, the conductors are flat conductors. Preferably their section is rectangular, the large side being greater than or equal to two and a half times the small side. The choice of flat conductors reduces the self-inductance of the system thus constructed. Finally, it is the necessary driving power which is reduced for establishing a field gradient. The temperature behavior of the whole of the apparatus is improved thereby.