| 摘要 |
PROBLEM TO BE SOLVED: To provide a holding existence detection device capable of preventing the wrong detection of holding something in a window glass even if sudden variations in supply voltage supplied to a motor for driving the window glass occurs by some other factors. SOLUTION: A processing circuit 2 outputs a pulse signal S3 of a pulse period TO corresponding to revolution speed of a motor M, periodic difference value ΔS is obtained by the pulse period TO of the pulse signal S3 from time to time and, at the same time, the basic threshold POS for making a holding decision is calculated from the average pulse period PO from time to time. The processing circuit 2 corrects the basic threshold POS in accordance with variations in supply voltage B from a battery BT. The processing circuit 2 compares the periodic difference value ΔS with the basic threshold POS, decision is made whether something is held in a window glass or not when the window glass is closed, and the motor M is inverted through a driving circuit 5 to drive when something is held. |
