| 摘要 |
PURPOSE:To form the high quality electronic balance inexpensively, by providing a coil for a constant positive load which generates a specified positive load on the side of a point, of force. CONSTITUTION:When a body of e.g. 100.1234g is mounted on a pan, a fine coarse switch S1 is switched to the coarse measuring side by a control part 15, and the output of an AD converter becomes 110.123 counts. A counted value of 10,000 counts for a zero point is subtracted by the computation in the control part, and the weight of the body on the pan is measured as about 100g. Then a step motor driving circuit 16 is actuated, and a pulse motor 8 is rotated so that an enclosed weight corresponding to 100g is disengaged. At the same time, the switch S1 is returned to the fine measuring side, and the output of 11,234 counts of the AD converter at this time is measured. The counted value of 10,000 for the zero point is subtracted, and 1,234 counts, i.e. 0.1234g is the finely measured part. The weight value is added to this value, and the weight of the body on the pan is computed as 100.1234, and ''100.1234g'' is displayed. |
