| 摘要 |
<p>A balance of the type provided with a permanent magnet system having an air gap, and a coil carrier arranged in the gap so that when a compensation current is supplied to the coil the load pan and its load to be weighed are compensated by the motor effect of the current, is provided according to the invention with at least one ferromagnetic member secured to the load-receiving means in the region of the permanent magnet field, whereby at least an approximate compensation for a pre-load is obtained. The heating effect of coil current is thereby lessened, permitting higher accuracy of weighing. Advantageously the ferromagnetic member is secured to the coil carrier, and comprises a set of members in rotationally symmetrical arrangement. When the members and the magnet system have corresponding-mutually-compensating temperature coefficients of magnetic performance, a highly precise apparatus is realised.</p> |
