Patent ID: 7218069

Claim:
A door opening/closing device that moves a door by a motor, comprising: an ideal-current calculating unit configured to calculate an ideal current for moving the door at a target speed; a actual-current calculating unit configured to calculate an actual current to be actually supplied to the motor based on the ideal current and present speed of the door, wherein the actual-current calculating unit calculates the actual current at a predetermined cycle; a current adding unit configured to determine whether an actual current calculated in a present cycle is larger than an actual current calculated in a previous cycle, and to add, when the actual current calculated in the present cycle is determined to be larger than the actual current calculated in the previous cycle, a current difference between the actual current calculated in the present cycle and the actual current calculated in a previous cycle to a total current difference obtained by adding current differences that have been calculated; a first determining unit configured to determine that a first condition is satisfied when the total current difference exceeds a threshold; a door-speed detecting unit configured to detect a speed of the door, wherein the door-speed detecting unit detects the speed of the door at a predetermined cycle; a door-speed adding unit configured to determine whether a speed of the door detected in a present cycle is lower than a speed of the door detected in a previous cycle, and to add, when the speed of the door detected in the present cycle is determined to be lower than the speed of the door detected in the previous cycle, a speed difference between the speed of the door detected in the present cycle and the speed of the door detected in the previous cycle to a total speed difference obtained by adding speed differences that have been calculated; a second determining unit configured to determine that a second condition is satisfied when the total speed difference exceeds a threshold; a rotation detecting unit configured to detect a rotation speed of the motor, wherein the rotation detecting unit detects the rotation speed at a predetermined cycle; a rotation-speed adding unit configured to determine whether a rotation speed detected in a present cycle is lower than a rotation speed detected in a previous cycle, and to add, when the rotation speed detected in the present cycle is determined to be lower than the rotation speed detected in the previous cycle, a rotation difference between the rotation speed detected in the present cycle and the rotation speed detected in the previous cycle to a total rotation difference obtained by adding rotation differences that have been calculated; a third determining unit configured to determine that a third condition is satisfied when the total rotation difference exceeds a threshold; a pinch determining unit configured to determine whether a foreign matter is caught in the door based on determination by the first determining unit, the second determining unit, and the third determining unit.