| 摘要 |
<p>The present invention employs an inexpensive method and apparatus for media height sensing. A sheet fed media-using-machine (63) has a media holder (64). The media holder (64) holds a stack (24) of a variable quantity of sheets of a medium to be supplied to a media-using-machine (63). The media holder (64) has a structure (30) for supporting the sheets and has a stack pusher (32) which may be a mechanical device that pushes the stack into a position such that said media-using-machine (63) may withdaw the sheets from said stack (24). The stack pusher (32) has a variable position within a range of motion wherein such position is dependent upon a quantity of sheets in the stack (24). A variable device (40) is attached to the stack pusher such that an electrical property of said variable device varies in relation to said position thereby allowing calculation of an estimate of the quantity of sheets in said stack (24), where the calculation is performed using said electrical property. The variable device (40) may be, for example, a capacitor or a resistor, and the electrical property being capacitance or resistance, respectively.</p> |
