| 摘要 |
<p>PURPOSE:To detect coordinates precisely by using a load detector having such a structure that a rectangular elastic plate equipped with plural strain sensors is fixed to an input board at four lengthwise both-end points of the two widest surfaces across spacers made of elastic bodies. CONSTITUTION:When an external force is applied to a proper position of the input board 6, the force is applied to the load detector between the input board 6 and a frame 7 and the elastic plate 1 flexes. When the external force is perpendicular to the input board 1. the elastic plate 1 deforms symmetrically about its center line. Then, strain sensors 2a and 2b increase and decrease in resistance value by the same value respectively. Consequently, one of voltages Va1 and Vb12 rises and the other falls, so the output Vf1 of a subtracter 9 is proportional to the load value. Further, spacers 4a-4d transmit the force to the elastic plate 1 downward uniformly, so the neutral surface of the deformation is constant regardless of whether the load is large or small and the output Vf1 is proportional to the load value over a wide range.</p> |
