| 摘要 |
<p>PURPOSE:To enhance the durability by constituting the device so that a pinball can be detected by using a matrix sensor along the board surface. CONSTITUTION:The device is provided with a face-like matrix sensor 20 in which plural parallel turn-back-like transmitting lines 22 are attached to one face of a glass board, plural parallel turn-back-like receiving lines 26 whose electromagnetic characteristics is varied by approach of a pinball B are coupled electromagnetically in the direction intersecting with the transmitting lines 22 and placed on the opposite face of the glass board, and having a detection unit 20A in the surrounding part of each transmission line 22 and each receiving line 26, a transmitting circuit 40 of each transmission line 22, a receiving circuit 50 of each receiving line 26, an offset means 30a for updating and storing successively a value of a signal from the receiving circuit 50 as an offset value for every detection unit 20a, an arithmetic means 30b for deriving a difference of a value of a signal from the receiving circuit and an offset value before updating, as an absolute value, and a comparing means 30c for comparing the absolute value with a set value, and sending a detecting signal related to the detection unit, when magnitude of the absolute value is above the set value. In such a way, the pinball can be detected on its board surface.</p> |
