Apparatus for determining imbalance in 120 degree spaced components and method of correcting said imbalance

Claim 2

In a method of eliminating imbalances in rotors, with which a compensation of masses by removing material is carried out in components displaced by 120*, and with which further material is subsequently removed in components displaced by 60* with respect to the former components, in case only limited material is available for removal, the improvement wherein, if the amount of initial imbalance in a first component exceeds the amount of material available for removal in this component, the removal of the maximum possible amount of material is effected leaving a residual amount still to be eliminated in this component, and material is removed in a second adjacent component displaced by 120* until in this component, too, an amount of imbalance has been obtained equal to said residual amount, and that the imbalance resulting from these two residual amounts is eliminated by removing material in a third component displaced by 60* with respect to both said first and second components.

Claim 3

In a method of eliminating imbalances in rotors, with which a compensation of masses by removing material is carried out in components displaced by 120*, and with which further material is subsequently removed in components displaced by 60* with respect to the former components, in case only limited material is available for removal, the improvement wherein, if the amount of initial imbalance is a first component exceeds the amount of material available for removal in this component, the removal of the maximum possible amount of material is effected leaving a residual amount still to be eliminated in this component, and if the amount of initial imbalance determined in a second adjacent component displaced by 120* is smaller than the residual amount left in the former component, an amount of material corresponding to this differential amount is removed in a component displaced by 180* with respect to the adjacent component, and an amount of material corresponding to the residual amount left in the former component is removed in a component lying on an angle bisector between the former and the adjacent component so that the residual imbalance left after the first removal of material is eliminated.

Claim 4

In a method of eliminating imbalances in rotors, with which a compensation of masses by removing material is carried out in components displaced by 120*, and with which further material is subsequently removed in components displaced by 60* with respect to the former components, in case only limited material is available for removal, the improvement wherein, if the amount of initial imbalance is a first component exceeds the amount of material available for removal in this component, the removal of the maximum possible amount of material is effected leaving a residual amount still to be eliminated in this component, and if the amount of initial imbalance determined in a second adjacent component displaced by 120* is smaller than the residual amount left in the former component, an amount of material corresponding to this differential amount is removed in a component displaced by 180* with respect to the adjacent component, and an amount of material corresponding to the residual amount left in the former component is removed in a component lying on an angle bisector between the former and the adjacent component so that the residual imbalance left after the first removal of material is eliminated.

Claim 5

An electrical circuit for determining the amounts of initial imbalance of a workpiece in two components displaced by 120* with respect to each other and determining the residual amounts which remain, after initial removal of material, in further components displaced by 60* with respect to said two components comprising: a component calculator for receiving electrical imbalance signals and providing first and second component output signals in components displaced 120* with respect to each other, means for providing a reference signal indicating the maximum amount of removable material in one component, a first comparator circuit for receiving said reference signal and said first output signal and for providing a difference signal representing the difference between said reference signal and said first output signal when said first output signal exceeds said reference signal, a second comparator circuit for receiving said receiving said reference signal and said second output signal and for providing a difference signal representing the difference between said reference signal and said second output signal when said second output signal exceeds said reference signal, a first subtraction circuit for receiving said difference signal from said first comparator circuit and subtracting that difference signal from said second output signal to produce a signal indicating the material to be removed in one component, and a second subtraction circuit for receiving said difference signal from said second comparator circuit and subtracting that difference signal from said first output signal to produce a signal indicating the amount of material to be removed in the second component.

Claim 6

An electrical circuit for determining the amounts of initial imbalance of a workpiece in two components displaced by 120* with respect to each other and determining the residual amounts which remain, after initial removal of material, in further components displaced by 60* with respect to said two components comprising: a component calculator for receiving electrical imbalance signals and providing first and second component output signals in components displaced 120* with respect to each other, means for providing a reference signal indicating the maximum amount of removable material in one component, a first comparator circuit for receiving said reference signal and said first output signal and for providing a difference signal representing the difference between said reference signal and said first output signal when said first output signal exceeds said reference signal, a second comparator circuit for receiving said receiving said reference signal and said second output signal and for providing a difference signal representing the difference between said reference signal and said second output signal when said second output signal exceeds said reference signal, a first subtraction circuit for receiving said difference signal from said first comparator circuit and subtracting that difference signal from said second output signal to produce a signal indicating the material to be removed in one component, and a second subtraction circuit for receiving said difference signal from said second comparator circuit and subtracting that difference signal from said first output signal to produce a signal indicating the amount of material to be removed in the second component.

Claim 7

A circuit as in claim 3 wherein each of said comparator circuits includes an output terminal for providing said difference signal.

Claim 8

A circuit as in claim 3 wherein each comparator circuit includes a pair of further output terminals each connected, via a diode conducting current in an opposite direction from the other diode of that pair, to receive said difference signal.

Claim 9

A circuit as in claim 5 wherein each comparator circuit includes a bridging circuit connected to said diodes for providing an output of one of said further terminals so long as said first and second output signal are less than said reference signal.