Structure for continuous monitoring of shaft vibration magnitude and phase angle

Claim 2

Structure for continuously monitoring vibration of an installed rotating shaft over a prolonged period comprising a first probe operably associated with the shaft for developing a sinusoidal electrical signal the amplitude of which is proportional to the velocity of radial movement of the shaft at the first probe in the direction of the first probe, a first operational amplifier connected to the first probe for receiving and amplifying the developed signal from the first probe, a rectifier connected in series with the first operational amplifier for rectifying the output thereof, an integrating circuit connected to the rectifier for integrating the rectified sinusoidal output from the first operational amplifier, a first variable resistance connected to the integrating circuit for receiving the output thereof, means for tapping a predetermined portion of the direct current output signal from the first variable resistance and means for recording the portion of the direct current output from the first variable resistance as a direct measure of shaft vibration magnitude, a second operational amplifier connected to receive the sinusoidal signal output of the first operational amplifier and providing a square wave output therefrom, a differentiating circuit connected to receive the square wave output signal of the first operational amplifier and to provide a pulsed output in response thereto, a second probe positioned adjacent the shaft, means for providing a pulse of electrical energy in the second probe each time the shaft completes a rotation relative to the second probe, a third operational amplifier connected to the second probe for sensing the pulses of electrical energy produced by the second probe and providing an output signal synchronized with the rotation of the shaft, a differentiating circuit for receiving the output signal from the third operational amplifier and providing a pulsed output in response thereto, a dual NOR gate flip-flop circuit connected to receive the differentiated square wave signal from the second operational amplifier and the differentiated signals from the third operational amplifier so that one side of the flip-flop circuit provides an output signal between the time a signal is provided at the one side of the flip-flop circuit from the third operational amplifier and the time a signal is provided at the flip-flop circuit on the other side thereof from the second operational amplifier, means for integrating the output signal from the one side of tHe flip-flop circuit to provide a direct current signal proportional thereto, a variable resistance for receiving the integrated output signal from the one side of the flip-flop circuit and means for tapping off a portion of the direct current signal from the second variable resistance and for recording the portion of the signal from the second variable resistor as a direct indication of the phase angle of the vibration of the shaft.

Claim 3

A plurality of structures as set forth in claim 1 positioned in spaced apart locations longitudinally of the shaft whereby continuous recording of the magnitude of shaft vibration and phase angle of the shaft vibration may be simultaneously recorded at different points along the shaft over prolonged periods.

Claim 4

Structure as set forth in claim 1 wherein the signal from the first probe is fed into one side of the first operational amplifier, and further including a voltage divider, a bias power supply connected across the voltage divider and means for connecting a variable point of the voltage divider to the other side of the first operational amplifier whereby the output of the first operational amplifier may be reduced to zero with no input signal to the first operational amplifier from the first probe.

Claim 5

Structure as set forth in claim 1 and further including a voltage divider, a bias power supply connected across the voltage divider, means for connecting a variable point on the voltage divider between the integrating means receiving the output from the one side of the flip-flop circuit and the second variable resistor whereby the output signal of the flip-flop circuit to the voltage divider can be maintained at zero with a zero input to the one side of the flip-flop circuit.

Claim 6

Structure as set forth in claim 1 wherein the first probe is an electromagnetic velocity sensitive probe secured to a mounting bearing for the shaft.

Claim 7

Structure as set forth in claim 1 wherein the second probe is a light sensitive probe and means are provided on the shaft adjacent the second probe for abruptly changing the light reflective qualities of the shaft at one location around the circumference thereof.

Claim 8

A plurality of structures for continuously monitoring vibration of an installed rotating shaft at a plurality of locations along the length thereof over a prolonged period each comprising a first electromagnetic velocity sensitive probe secured to a mounting bearing for the shaft for developing a sinusoidal electrical signal the amplitude of which is proportional to the velocity of radial movement of the shaft at the first probe in the direction of the first probe, a first operational amplifier connected to the first probe for receiving and amplifying the developed signal from the first probe at one side thereof, a first voltage divider, a bias power supply connected across the first voltage divider and means for connecting a variable point of the first voltage divider to the other side of the first operational amplifier, whereby the output of the first operational amplifier may be reduced to zero with no input signal to the first operational amplifier from the first probe, a rectifier connected in series with the first operational amplifier for rectifying the output thereof, an integrating circuit connected to the rectifier for integrating the rectified sinusoidal output from the first operational amplifier, a first variable resistance connected to the integrating circuit for receiving the output thereof, means for tapping off a predetermined portion of the direct current output signal from the first variable resistance and means for recording the portion of the direct current output from the first variable resistance as a direct measure of shaft vibration magnitude, a second operational amplifier connected to receive the sinusoidal signal output of the first operational amplifier and providing a square wave output therefrom, a differentiating circuit connected to receive the square wave output signal of the first operational amplifier and to provide a pulsed output in response thereto, a second light sensitive probe positioned adjacent the shaft, means for abruptly changing the light reflective qualities of the shaft at one location around the circumference thereof for providing a pulse of electrical energy in the second probe each time the shaft completes a rotation relative to the second probe, a third operational amplifier connected to the second probe for sensing the pulses of electrical energy produced by the second probe and providing an output signal synchronized with the rotation of the shaft, a differentiating circuit for receiving the output signal from the third operational amplifier and providing a pulsed output in response thereto, a dual NOR gate flip-flop circuit connected to receive the differentiated square wave signal from the second operational amplifier and the differentiated signals from the third operational amplifier so that one side of the flip-flop circuit provides an output signal between the time a signal is provided at the one side of the flip-flop circuit from the third operational amplifier and the time a signal is provided at the flip-flop circuit on the other side thereof from the second operational amplifier, means for integrating the output signal from the one side of the flip-flop circuit to provide a direct current signal proportional thereto, a second variable resistance for receiving the integrated output signal from the one side of the flip-flop circuit, a second voltage divider, a bias power supply connected across the second voltage divider, means for connecting a variable point on the second voltage divider between the integrating means receiving the output from the one side of the flip-flop circuit and the second variable resistor whereby the output signal of the flip-flop circuit to the second voltage divider can be maintained at zero with a zero input to the one side of the flip-flop circuit, and means for tapping off a portion of the direct current signal from the second variable resistance and for recording the portion of the signal from the second variable resistor as a direct indication of the phase angle of the vibration of the shaft.

Claim 9

A plurality of structures for continuously monitoring vibration of an installed rotating shaft at a plurality of locations along the length thereof over a prolonged period each comprising a first electromagnetic velocity sensitive probe secured to a mounting bearing for the shaft for developing a sinusoidal electrical signal the amplitude of which is proportional to the velocity of radial movement of the shaft at the first probe in the direction of the first probe, a first operational amplifier connected to the first probe for receiving and amplifying the developed signal from the first probe at one side thereof, a first voltage divider, a bias power supply connected across the first voltage divider and means for connecting a variable point of the first voltage divider to the other side of the first operational amplifier, whereby the output of the first operational amplifier may be reduced to zero with no input signal to the first operational amplifier from the first probe, a rectifier connected in series with the first operational amplifier for rectifying the output thereof, an integrating circuit connected to the rectifier for integrating the rectified sinusoidal output from the first operational amplifier, a first variable resistance connected to the integrating circuit for receiving the output thereof, means for tapping off a predetermined portion of the direct current output signal from the first variable resistance and means for recording the portion of the direct current output from the first variable resistance as a direct measure of shaft vibration magnitude, a second operational amplifier connected to receive the sinusoidal signal output of the first operational amplifier and providing a square wave output therefrom, a differentiating circuit connected to receive the square wave output signal of the first operational amplifier and to provide a pulsed output in response thereto, a second light sensitive probe positioned adjacent the shaft, means for abruptly changing the light reflective qualities of the shaft at one location around the circumference thereof for providing a pulse of electrical energy in the second probe each time the shaft completes a rotation relative to the second probe, a third operational amplifier connected to the second probe for sensing the pulses of electrical energy produced by the second probe and providing an output signal synchronized with the rotation of the shaft, a differentiating circuit for receiving the output signal from the third operational amplifier and providing a pulsed output in response thereto, a dual NOR gate flip-flop circuit connected to receive the differentiated square wave signal from the second operational amplifier and the differentiated signals from the third operational amplifier so that one side of the flip-flop circuit provides an output signal between the time a signal is provided at the one side of the flip-flop circuit from the third operational amplifier and the time a signal is provided at the flip-flop circuit on the other side thereof from the second operational amplifier, means for integrating the output signal from the one side of the flip-flop circuit to provide a direct current signal proportional thereto, a second variable resistance for receiving the integrated output signal from the one side of the flip-flop circuit, a second voltage divider, a bias power supply connected across the second voltage divider, means for connecting a variable point on the second voltage divider between the integrating means receiving the output from the one side of the flip-flop circuit and the second variable resistor whereby the output signal of the flip-flop circuit to the second voltage divider can be maintained at zero with a zero input to the one side of the flip-flop circuit, and means for tapping off a portion of the direct current signal from the second variable resistance and for recording the portion of the signal from the second variable resistor as a direct indication of the phase angle of the vibration of the shaft.