| 摘要 |
PURPOSE:To allow to restore normal operating condition of coal transfer device, by slightly rotating the rotor of the rotary valve of a coal transfer device backwardly, when the rotor is stalled by biting foreign materials mingled in the coal, then driving forward as normal. CONSTITUTION:In the process of taking out the coal in the hopper 1 by normal rotation of the rotor 4 of the rotary valve 7, if a wooden piece, etc., are bitten within the valve 7, load of the motor 6 rotating the rotor 4, increases. Therefore, the stall relay 10, which is made to detect the load of the motor 6 and to issue stalling signal, makes both switches F, R of the switching gear 9 to open the circuit and stops the motor 6. After the switch F is opened, and after a set time of the timer T1 is passed, the switch E is closed, and the rotor 4 is rotated by the motor 6 to reverse direction for about 45 deg.. Then the motor 6 is stopped after set time of the timer T2, and the switch F is closed after set time of the timer T3 is passed, and the motor 6 resumes normal rotation. |
