Method and apparatus for developing balance information for rotating equipments and assemblies

A system for locating the unbalance and determining the signal phase of vibration data signals relative to tachometer point signals of a rotating member comprising,

• means for determining the amplitudes of the unbalance signals of the vibration data signals and providing amplitude output signals,
• means responsive to said amplitude output signals for generating balancing signals having a frequency of the tachometer point signals and the amplitude of the unbalance signals,
• means for nulling the balancing signals and the unbalance signals and providing summing output signals,
• means for shifting the phase of the balancing signals to null the unbalance signals in said nulling means,
• means for determining said shifted phase,
• said balancing signal generating means including sine converter means for generating balancing signal sine waves,
• means for providing tach signals that are phase coherent with the tachometer point signals and the unbalance signals and phase pulses that are phase coherent with the tach signals,
• said phase shifting means including analyzer means responsive to said tach signals and said summing output signals for providing a plurality of analyzer output signals the amplitude of which increase and decrease with the amplitude of said summing output signals,
• detector means for detecting the amplitude of particular output signals of said analyzer means,
• said detector means including means for determining changes and no changes in amplitude of said analyzer output signals and providing a given number of output pulses depending upon the changes in the amplitude,
• phase counters for receiving said detector means output pulses as pre-load counts,
• and means for feeding said phase pulses into said phase counters for counting out said phase counters providing a carry pulse to said sine converter means at a timing that sets said shifted phase.

In a method for developing balance information for an unbalanced rotating member from tachometer point signals and vibration pickup unbalanced signals, where the phase difference of the unbalanced signals to the tachometer signals establishes location of the unbalance, comprising the steps of,

• determining the amplitude of the unbalanced signals,
• generating balancing signals that are frequency and phase coherent with the tachometer point signals and have the amplitude of the unbalanced signals,
• shifting the phase of the balancing signals to null the unbalance signals in a summing device,
• and determining the phase of the balancing signals relative to the tachometer point signals that nulls the unbalanced signals giving the phase shift location of the unbalance.

A system for locating the unbalance and determining the signal phase of vibration data signals relative to tachometer point signals of a rotating member comprising,

• means for determining the amplitudes of the unbalance signals of the vibration data signals and providing amplitude output signals,
• means responsive to said amplitude output signals for generating balancing signals having the frequency of the tachometer point signals and the amplitude of the unbalance signals,
• means for nulling the balancing signals and the unbalance signals and providing summing output signals,
• means for shifting the phase of the balancing signals to null the unbalance signals in the nulling means,
• means for determining said shifted phase,
• said balancing signal generating means including sine converter means for generating balancing signal sine waves,
• and means for timing said balancing signal sine waves to be phase coherent with the tachometer point signals prior to shifting the phase of said balancing signal sine wave by said phase shifting means.