Ridge vent with biocidal source
A balance monitoring system utilizes existing Z-axis servo motor and control features of a machine tool to sense disturbances directly related to rotary table imbalance. It has been found that a Z-axis following error signal is the most noise free and most asily correlated axis control indictor. Since the Z-axis following error signal is already available using existing hardware and software, there is no need for additional transducers or devices. The balance monitoring of system can be used for three different purposes; for monitoring table balance at startup of the rotary table, for diagnosing table balance, and for in-process monitoring during a turning operation.
1 . A method for detecting a load imbalance in a rotary table, or in a workpiece carried by a rotary table, in which the table is mounted for linear movement along a linear axis relative to machine tool, the method comprising the steps of:
using a position command signal to position the rotary table along said linear axis by means of a servo mechanism;
generating a position feedback signal indicative of the location of the rotary table after positioning by means of the servo mechanism;
generating a following error signal for said linear axis by subtracting the position feedback signal from the position command signal; and,
detecting disturbances in the following error signal indicative of the load imbalance.
2 . A method for using a servo mechanism to detect a load imbalance in a rotary table, or in a workpiece carried by a rotary table, in which the table is mounted for linear movement along a linear axis relative to machine tool, the method comprising the steps of:
using a position command signal to the servo mechanism to position the rotary table along said linear axis;
using the servo mechanism to generate a position feedback signal indicative of the location of the rotary table after positioning by the servo mechanism;
generating a following error signal for said linear axis by subtracting the position feedback signal from the position command signal; and,
detecting disturbances in the following error signal indicative of the load imbalance.
3 . A method of detecting an imbalance in a rotary table, in which the table is mounted for linear movement along a linear axis by means of a servo mechanism, the method comprising the steps of:
detecting the servo mechanism following error signal;
detecting a disturbance in the following error signal; and,
using the disturbance in the linear axis following error signal to indicate an imbalance in the rotary table.
4 . The method of claim 3 further comprising the steps of:
setting a predetermined limit for the magnitude of allowable disturbance in the linear axis following error signal;
determining if the disturbance in the linear axis following error signal exceeds said predetermined limit as the rotational velocity of the table is increased; and,
generating an alarm if the disturbance in the linear axis following error signal exceeds said predetermined limit.
5 . The method of claim 4 further comprising the steps of:
generating a velocity signal indicative of the speed of rotation of the rotary table;
comparing the velocity signal to a predetermined operational speed signal for the rotary table; and,
switching to a process monitor mode if the velocity signal exceeds the predetermined operational speed signal for the rotary table without generating an alarm.
6 . A method of diagnosing an imbalance in a rotary table, in which the table is mounted for linear movement along a linear axis by means of a servo mechanism, the method comprising the steps of:
generating a signal indicative of the B-axis velocity of the rotary table;
generating a signal indicative of the B-axis position of the rotary table;
detecting the servo mechanism following error signal;
detecting a disturbance in the following error signal; and,
generating a signal indicative of the peaks of the linear axis following error signal and correlating said peaks with the signal indicative of the B-axis position of the rotary table.
7 . The method of claim 6 further comprising the steps of:
generating a signal indicative of the amplitude of the peaks of the linear axis following error signal;
generating a phase display to indicate the phase of the imbalance and amplitude display to indicate the amplitude of the imbalance; and,
correlating the two displays to indicate the steps needed to balance the rotary table.
8 . A method of monitoring a turning operation in which a workpiece is rotated by means of a rotary table, a cutting tool engages the workpiece while it is rotating, and the table is mounted for linear movement along a linear axis by means of a servo mechanism while the workpiece is rotating, the method comprising the steps of:
generating a signal indicative of the B-axis velocity of the rotary table;
using the servo mechanism to move the rotary table along said linear axis;
detecting the Z-axis velocity of the rotating table;
detecting the servo mechanism following error signal for motion of the rotary table along the linear axis;
providing a limit signal for the servo mechanism following error signal;
detecting a disturbance in the following error signal; and,
comparing the disturbance in the following error signal to the limit signal.
9 . The method of claim 8 further comprising the steps of:
activating an alarm if the following error signal exceeds the limit signal.