DETECTION DEVICE AND DETECTION SYSTEM
A detection device according to an embodiment detects a presence or absence of a processing material adhered to an interior wall of a drum of a mill pulverizing a mineral. The detection device is configured to store an initial torque detected at a preset initial rotation angle, calculate a maximum torque based on the initial torque, the initial rotation angle, and a rotation angle greater than the initial rotation angle, calculate a ratio of a torque at the rotation angle divided by the maximum torque, compare the ratio and a preset threshold, and determine that the processing material is adhered to the interior wall of the drum when the ratio is equal to the threshold or greater than the threshold.
1 . A detection device detecting a presence or absence of a processing material adhered to an interior wall of a drum at a startup of a mill pulverizing a mineral, the detection device being configured to:
store an initial torque when a processing material is adhered to the interior wall of the drum, the initial torque being detected at an initial rotation angle of the drum, the initial rotation angle being prescribed;
calculate a maximum torque at a rotation angle greater than the initial rotation angle when the processing material is adhered to the interior wall of the drum based on the initial torque, the initial rotation angle, and the rotation angle;
calculate a ratio of a torque detected at the rotation angle divided by the maximum torque;
compare the ratio and a preset threshold;
determine that the processing material is not adhered to the interior wall of the drum when the ratio is less than the threshold; and
determine that the processing material is adhered to the interior wall of the drum when the ratio is equal to the threshold or greater than the threshold after the rotation angle of the drum has reached a first rotation angle at which the processing material can detach and fall from the interior wall of the drum, the first rotation angle being greater than the initial rotation angle.
2 . The detection device according to claim 1 , wherein
the calculating of the maximum torque is a calculation according to Formula (1), wherein Tmax is the maximum torque, TL is the initial torque, θ is the rotation angle, and θL is the initial rotation angle.
T max= TL ×(sin θ/sin θ L ) (1)
3 . The detection device according to claim 1 , further comprising:
generating a command to stop an operation of the mill when it is determined that the processing material is adhered to the interior wall of the drum.
4 . The detection device according to claim 1 , further comprising:
generating a command to cause an operation of the mill to be the processing material removal operation when it is determined that the processing material is adhered to the interior wall of the drum.
5 . A detection system, comprising:
the detection device according to claim 1 ;
an electric motor driving the drum of the mill;
a drive device driving the electric motor;
a rotation angle detector detecting a rotation angle of the electric motor; and
a torque detector detecting a torque output by the drive device,
the mill being one of a ball mill, a SAG mill, or an AG mill,
the rotation angle detector successively detecting the rotation angle and transmitting the rotation angle to the detection device,
the torque detector detecting the initial torque and transmitting the initial torque to the detection device, and successively detecting the torque at the rotation angle and transmitting the torque to the detection device,
the detection device calculating the ratio, comparing the ratio and the threshold, and determining a magnitude relationship between the ratio and the threshold each time the detection device receives the torque at the rotation angle.