Vibration isolation
AssigneeBAE SYSTEMS plc
InventorsFREDERICK A. JOHNSON, STEPHEN DALEY
Life of this patent
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Abstract
A support for machinery, and for isolating vibration from the machinery, comprises a plurality of mounts, each mount comprising an elastomeric block for completely supporting the static load of the machinery, and active isolation means comprising inertial shakers arranged to maintain essentially a zero stiffness of the mount to excited structural resonances over a desired frequency band above said mount resonant frequency, and to modify the transmission of out of balance forces to the hull. A control system coupled to the inertial shakers includes a means for applying damping force signals, such as to dampen structural resonances, to inhibit the onset of resonant vibration.
Claims13
A method for mounting machinery, and for isolating vibration therefrom, the method comprising:
- (a) supporting said machinery by means of a support that includes a plurality of resilient mounts, each mount comprising a passive resilient means for fully supporting the static load of the machinery, and active isolation means;
- and
- (b) controlling said active isolation means of each said mount, the controlling comprising:
- (i) sensing motion of the support;
- (ii) filtering, from the sensed motion, displacement arising from excited resonances, to determine the motion of the mount due to rigid body modes of motion;
- (iii) calculating modal restoring forces;
- and
- (iv) applying local demand forces to each said resilient mounts for compensating for rigid body modes of motion;
- controlling said active isolation means being arranged such that:
- (i) below the mount resonant frequency a performance parameter of each mount is essentially that of the passive resilient means;
- and
- (ii) above the mount resonant frequency and over a desired frequency band, essentially a zero stiffness of each mount is maintained to excited structural resonances.
-25. (canceled)
A machine readable medium comprising machine-executable instructions for performing a method for isolating vibration from machinery supported by a support that includes a plurality of resilient mounts, each mount comprising a passive resilient means for fully supporting the static load of the machinery, and active isolation means;
- the method comprising:
- controlling said active isolation means of each said mount, the controlling comprising:
- (i) sensing motion of the support;
- (ii) filtering, from the sensed motion, displacement arising from excited resonances, to determine the motion of the mount due to rigid body modes of motion;
- (iii) calculating modal restoring forces;
- and
- (iv) applying local demand forces to each said resilient mounts for compensating for rigid body modes of motion;
- the controlling said active isolation means being arranged such that:
- (i) below the mount resonant frequency a performance parameter of each mount is essentially that of the passive resilient means;
- and
- (ii) above the mount resonant frequency and over a desired frequency band, essentially a zero stiffness of each mount is maintained to excited structural resonances.
A method for mounting machinery, and for isolating vibration therefrom, the method comprising:
- (a) supporting said machinery by a support that includes a plurality of resilient mounts, each mount comprising a passive resilient support for fully supporting the static load of the machinery, and an active isolator;
- and
- (b) controlling said active isolator of each said mount, the controlling comprising:
- (i) sensing motion of the support;
- (ii) filtering, from the sensed motion, displacement arising from excited resonances, to determine the motion of the mount due to rigid body modes of motion;
- (iii) calculating modal restoring forces;
- and
- (iv) applying local demand forces to each said resilient mounts for compensating for rigid body modes of motion;
- the controlling said active isolator of each said mount being arranged such that:
- (i) below the mount resonant frequency a performance parameter of each mount is essentially that of the passive resilient support;
- and
- (ii) above the mount resonant frequency and over a desired frequency band, essentially a zero stiffness of each mount is maintained to excited structural resonances.
A machine readable medium comprising machine-executable instructions for performing a method for isolating vibration from machinery supported by a support that includes a plurality of resilient mounts, each mount comprising a passive resilient support for fully supporting the static load of the machinery, and an active isolator means;
- the method comprising:
- controlling said active isolator of each said mount, the controlling comprising:
- (i) sensing motion of the support;
- (ii) filtering, from the sensed motion, displacement arising from excited resonances, to determine the motion of the mount due to rigid body modes of motion;
- (iii) calculating modal restoring forces;
- and
- (iv) applying local demand forces to each said resilient mounts for compensating for rigid body modes of motion;
- the controlling said active isolator being arranged such that:
- (i) below the mount resonant frequency a performance parameter of each mount is essentially that of the passive resilient support;
- and
- (ii) above the mount resonant frequency and over a desired frequency band, essentially a zero stiffness of each mount is maintained to excited structural resonances.
Dependencies are inferred from the claim text.