Patent Description:
A bearing support system includes a bearing housing, a bearing disposed within the bearing housing to receive and support rotation of a shaft about an axial axis, and a bearing damper disposed around the bearing. The bearing damper comprises a knitted wire mesh pad having a length in an axial direction that is parallel to the axial axis and a wall thickness in a radial direction that is transverse to the axial axis. The bearing support system also includes a compression ring positioned to be movable relative to the bearing housing in the axial direction such that a movement of the compression ring in the axial direction applies a compression to the bearing damper. The compression applied to the bearing damper results in a change in at least one of the length and wall thickness of the knitted wire mesh pad and a corresponding change in a stiffness and a damping of the bearing damper. The system includes an actuator coupled to the compression ring and controllable to move the compression ring in the axial direction in response to mechanical vibrations in an environment of the bearing damper. The actuator comprises a worm drive. The system may include an anti-rotation ring disposed between the compression ring and the bearing damper and anti-rotatably engaging the bearing housing. The movement of the compression ring in the axial direction may result in a movement of the anti-rotation ring in the axial direction. The system may include a structural support coupled to the bearing housing. The structural support may have a support wall disposed at least partially within the bearing housing such that an annular space is defined between the support wall and the bearing housing. The bearing may be disposed at a first side of the support wall, the bearing damper may be disposed at a second side of the support wall in a first portion of the annular space, and the compression ring may be disposed in a second portion of the annular space. The compression ring may be in threaded engagement with the bearing housing. The compression ring may be movable in the axial direction by adjustment of the threaded engagement. The system may include a shoulder formed on at least one of the support wall and the bearing housing. The bearing damper may be constrained between the shoulder and the anti-rotation ring. The actuator coupled to the compression ring may be a worm drive. The worm drive may comprise a worm gear that is coupled to the compression ring and a worm screw that meshes with the worm gear. The system may include a split wedge ring disposed between the anti-rotation ring and the bearing damper to apply a compression to the bearing damper in the radial direction in response to movement of the compression ring in the axial direction. The system may include at least one vibration sensor positioned to sense the mechanical vibrations in the environment of the bearing damper. The at least one vibration sensor may be coupled to the bearing housing or to the shaft. The system may include a controller in communication with the at least one vibration sensor. The controller may receive an output of the at least one vibration sensor and control the actuator to move the compression ring in the axial direction based on the output of the at least one vibration sensor. The knitted wire mesh pad may be made of one or more wires, each wire including a metal or an alloy.

A method of supporting rotation of a shaft in a machine includes providing a bearing within a bearing housing and disposing a bearing damper around the bearing. The bearing damper comprises a knitted wire mesh pad having a length in an axial direction that is parallel to an axial axis and a wall thickness in a radial direction that is transverse to the axial axis. The method includes receiving and supporting a shaft in the bearing, rotating the shaft about the axial axis, measuring vibrations in an environment of the damper during rotation of the shaft, and applying compression to the bearing damper to adjust at least one of the length and wall thickness of the bearing damper based on the measured vibrations. The act of applying compression to the bearing damper includes moving a compression ring relative to the bearing housing in the axial direction. The act of applying compression to the bearing damper may include determining an amount by which to adjust at least one of the axial length and the wall thickness of the knitted wire mesh pad based on the measured vibrations. The act of applying compression to the bearing damper may include determining a change in the measured vibrations over a time period and applying the compression if the change in measured vibrations over the time period exceeds a threshold. The act of moving the compression ring relative to the bearing housing in the axial direction may include controlling an actuator to move the compression ring in the axial direction. The act of applying compression to the bearing damper based on the measured vibrations includes transferring movement of the compression ring in the axial direction to an anti-rotation ring that is in abutting relation with the knitted wire mesh pad. The act of applying compression to the bearing damper based on the measured vibrations may include applying compression to the knitted wire mesh pad along the axial direction and the radial direction.

The foregoing general description and the following detailed description are exemplary of the invention and are intended to provide an overview or framework for understanding the nature of the invention as it is claimed. The accompanying drawings are included to provide further understanding of the invention and are incorporated in and constitute a part of the specification. The drawings illustrate various embodiments of the invention and together with the description serve to explain the principles and operation of the invention.

The following is a description of the figures in the accompanying drawings. In the drawings, identical reference numbers identify similar elements or acts. The sizes and relative positions of elements in the drawings are not necessarily drawn to scale. For example, the shapes of various elements and angles are not necessarily drawn to scale, and some of these elements may be arbitrarily enlarged and positioned to improve drawing legibility. Further, the particular shapes of the elements as drawn are not necessarily intended to convey any information regarding the actual shape of the particular elements and have been solely selected for ease of recognition in the drawing.

In the following detailed description, certain specific details are set forth in order to provide a thorough understanding of various disclosed implementations and embodiments. However, one skilled in the relevant art will recognize that implementations and embodiments may be practiced without one or more of these specific details, or with other methods, components, materials, and so forth. In other instances, well known features or processes associated with bearing support systems have not been shown or described in detail to avoid unnecessarily obscuring descriptions of the implementations and embodiments. For the sake of continuity, and in the interest of conciseness, same or similar reference characters may be used for same or similar objects in multiple figures.

<FIG> shows an exemplary bearing support system <NUM> that may be used to support rotation of a shaft about an axial axis <NUM>. System <NUM> includes a bearing housing <NUM> and a structural support <NUM>. Bearing housing <NUM> and structural support <NUM> may be part of a machine. Bearing housing <NUM> and structural support <NUM> may have a common axial axis, which may be aligned with axial axis <NUM>. Structural support <NUM> has an inner support wall <NUM> and an outer support wall <NUM>. Each of inner support wall <NUM> and outer support wall <NUM> may be generally cylindrical in shape. Outer support wall <NUM> circumscribes a portion of inner support wall <NUM> and is radially spaced apart from inner support wall <NUM>. One end of inner support wall <NUM> is joined to one end of outer support wall <NUM> by an end wall <NUM>. The other end of outer support wall <NUM> that is not joined to end wall <NUM> terminates in an annular flange <NUM>. Annular flange <NUM> may be secured to bearing housing <NUM> by any suitable means, such as by bolts <NUM>. A portion of inner support wall <NUM> extends into and through a central bore <NUM> of bearing housing <NUM>. An inner collar <NUM> is formed on an inner surface of inner support wall <NUM>. Inner collar <NUM> provides a shoulder <NUM>. An outer collar <NUM> may be formed on an outer surface of inner support wall <NUM>. In one implementation, outer collar <NUM> is disposed radially of inner collar <NUM>, with inner support wall <NUM> serving as a separating wall between outer collar <NUM> and inner collar <NUM>. Outer collar <NUM> provides a shoulder <NUM>.

System <NUM> includes a bearing <NUM> disposed inside a central passage <NUM> defined by inner support wall <NUM>. Bearing <NUM> is illustrated as a rolling-element bearing, such as a ball bearing. However, other types of bearings may be used in the system. In one implementation, bearing <NUM> is disposed inside central passage <NUM> such that one end of bearing <NUM> abuts shoulder <NUM> provided by inner collar <NUM> of inner support wall <NUM>. Bearing <NUM> includes a hole <NUM> to receive a shaft that is to be rotated about axial axis <NUM>. <FIG> shows a shaft <NUM> fitted in hole <NUM> for illustration purposes. In <FIG>, bearing <NUM> circumscribes a portion of shaft <NUM> and thereby separates shaft <NUM> from inner support wall <NUM>. Bearing <NUM> supports shaft loads during rotation of shaft <NUM> about axial axis <NUM>. In one implementation, shaft <NUM> is a stepped shaft including a shoulder <NUM>. In this implementation, the other end of bearing <NUM> that is not in contact with support wall shoulder <NUM> abuts shaft shoulder <NUM> such that bearing <NUM> is retained between support wall shoulder <NUM> and shaft shoulder <NUM>.

Returning to <FIG>, system <NUM> includes a bearing damper <NUM> arranged on the outer surface of inner support wall <NUM> and in an annular space defined between opposing surfaces of inner support wall <NUM> and bearing housing <NUM>. One end surface of bearing damper <NUM> abuts shoulder 184a in bearing housing <NUM> and shoulder <NUM> on support wall <NUM>. Shoulder 184a of bearing housing <NUM> is aligned with shoulder 156a of support wall <NUM> to form a constraining wall for bearing damper <NUM> at one end. (In some cases, shoulder <NUM> on support wall <NUM> may be omitted, and the end surface of bearing damper <NUM> may abut only shoulder 184a in bearing housing as shown in <FIG>. ) A circumferential surface of bearing damper <NUM> abuts an inner wall 184b of bearing housing <NUM>. In one implementation, bearing damper <NUM> is used to absorb vibrations in the system and prevent damage to bearing <NUM>. In one implementation, bearing damper <NUM> is a wire mesh vibration damper including one or more knitted wire mesh pads (not identified separately). The knitted wire mesh pad is made by knitting a single wire or multiple wires to form a flexible wire mesh of interlocking loops. The knitting can be similar to techniques used to knit yarn. The resulting knitted wire mesh is formed into a desired shape with a hole in the center to allow the knitted wire mesh to be fitted around a tubular structure. The wires can be round or flat. The material of the wire may be a metal or an alloy, such as stainless steel, copper, steel, an aluminum alloy, or some combination thereof.

<FIG> shows bearing damper <NUM> with one knitted wire mesh pad <NUM> having a ring shape, an axial length L, and a wall thickness T. When bearing damper <NUM> is in bearing support system <NUM> as shown in <FIG>, the axial length L of knitted wire mesh pad <NUM> will be in a direction that is parallel to axial axis <NUM>. Wall thickness T may be in a radial direction that is transverse to axial axis <NUM>. <FIG> shows knitted wire mesh pad <NUM> with a straight wall. In some cases, knitted wire mesh pad <NUM> may have a tapered wall. Wall thickness T may be uniform or non-uniform along the circumference of the ring shape. In the configuration where bearing damper <NUM> has one knitted wire mesh pad <NUM>, the axial length of the bearing damper is the same as the axial length L of the knitted wire mesh pad <NUM>.

<FIG> shows bearing damper <NUM> with multiple knitted wire mesh pads, e.g., knitted wire mesh pads 180a, 180b, arranged in a stack. Each of knitted wire mesh pads 180a, 180b has an axial length L and a wall thickness T as described for knitted wire mesh pad <NUM> in <FIG>. The axial lengths of the knitted wire mesh pads in a stack may be the same or may be different. The wall thicknesses of the knitted wire mesh pads in a stack may be the same or may be different. In the configuration where bearing damper <NUM> has multiple knitted wire mesh pads, e.g., mesh pads 180a, 180b, in a stack, the axial length of the bearing damper is equal to a sum of the axial lengths of the knitted wire mesh pads in the stack.

The term "ring shape" as used with knitted wire mesh pad(s) may encompass a continuous ring shape that defines a circular hole in the middle as shown for knitted wire mesh pad <NUM> in <FIG>, a split ring shape that defines a circular hole in the middle as shown for knitted wire mesh pad <NUM>' in <FIG>, and ring segments arranged to form a ring shape that defines a circular hole as shown for knitted wire mesh pad <NUM>" in <FIG>. However, bearing damper <NUM> is not limited to knitted wire mesh pads having circular ring shapes. For example, <FIG> shows an example where bearing damper <NUM> includes a knitted wire mesh pad <NUM>‴ having a square shape that defines a circular hole in the middle.

In one implementation, the dimension of the hole in the middle of the knitted wire mesh pad(s) may be selected so that bearing damper <NUM> can fit around support wall <NUM> as shown in <FIG> and <FIG>. Also, the outer dimension of the knitted wire mesh pad(s) may be selected so that bearing damper <NUM> contacts both support wall <NUM> and bearing housing <NUM> as shown in <FIG> and <FIG>.

The knitted wire mesh pad (<NUM> in <FIG>) acts as a spring when subjected to compressive stress. The knitted wire mesh pad can be deformed along the axial length L direction and along the wall thickness T. In one example, the knitted wire mesh pad may have an initial axial length L<NUM> and an initial wall thickness T<NUM> prior to use in the system (<NUM> in <FIG> and <FIG>). Axial compression can be applied to knitted wire mesh pad <NUM>, which would result in a decrease in the axial length from the initial axial length L<NUM>. When the axial compression is removed, the wire mesh pad may return to its initial axis length L<NUM>. Similarly, radial compression can be applied to the knitted wire mesh pad <NUM>, which would result in a decrease in the wall thickness of the wire mesh pad from the initial wall thickness T<NUM>. When the radial compression is removed, the wire mesh pad may return to its initial wall thickness T<NUM>.

The stiffness and damping of bearing damper <NUM> will generally increase with increasing compression applied to the knitted wire mesh pad(s) in the damper. Stiffness is the extent to which a material resists deformation in response to applied force. Damping is a measure of the ability of a material to suppress mechanical vibrations. Materials with high damping are better able to suppress mechanical vibrations. For illustration purposes, <FIG> shows a relationship between axial compression applied to a knitted wire mesh pad and resulting stiffness of the knitted wire mesh pad. The numerical values of the stiffness, axial compression, and axial strain shown in <FIG> are not intended to be limiting since these would depend on the configuration of the knitted wire mesh pad. As shown in <FIG>, stiffness (K) of the knitted wire mesh generally increases as axial compression of the wire mesh increases. <FIG> shows a relationship between axial compression and viscous damping coefficient (C) for the example knitted wire mesh pad of <FIG>. As in the case of <FIG>, the numerical values shown in <FIG> are not intended to be limiting. As shown in <FIG>, viscous damping coefficient of the knitted wire mesh pad generally increases with increasing axial compression of the knitted wire mesh pad. After a certain threshold, additional increases in axial compression may not result in additional increases in viscous damping coefficient. In the example shown in <FIG>, viscous damping coefficient is practically constant for axial compression greater than <NUM> inches.

In <FIG> and <FIG>, bearing <NUM> is illustrated as a ball bearing or rolling-element bearing. However, system <NUM> is not limited to rolling-element bearing, and any type of bearing can be implemented. Other bearing supports or configurations besides what is shown in <FIG> and <FIG> may also be used. <FIG> shows an example where a hydrodynamic bearing <NUM>' may be used to support shaft <NUM>' instead of a rolling-element bearing. Hydrodynamic bearing <NUM>' includes a sleeve having a bore to receive shaft <NUM>' as shown. Lubricant (not shown) is provided in a clearance between the sleeve and shaft to support rotation of the shaft. In the example of <FIG>, hydrodynamic bearing <NUM>' is disposed inside a central passage defined by an inner surface of a support wall <NUM>' of a structural support <NUM>'. Bearing damper <NUM> is arranged on an outer surface of support wall <NUM>'. In this arrangement, support wall <NUM>' is between hydrodynamic bearing <NUM>' and bearing damper <NUM>.

<FIG> and <FIG> show a bearing support arrangement where bearing damper <NUM> is arranged in parallel with bearing <NUM>/structural support <NUM>, i.e., the stiffness and damping of bearing damper <NUM> are in parallel to the stiffness and damping of bearing <NUM>/structural support <NUM>. Similarly, in <FIG>, bearing damper <NUM> is arranged in parallel with bearing <NUM>'/structural support <NUM>', i.e., the stiffness and damping of bearing damper <NUM> are in parallel to the stiffness and damping of bearing <NUM>'/structural support <NUM>'. <FIG> shows an alternative bearing support arrangement where bearing damper <NUM> is arranged in series with bearing <NUM>. Bearing <NUM> in <FIG> is a rolling-element bearing. Similarly, <FIG> shows an alternative bearing support arrangement where bearing damper <NUM> is arranged in series with bearing <NUM>'. Bearing <NUM>' in <FIG> is a hydrodynamic bearing. Arranging bearing and bearing damper in series or in parallel can be applied to any type of bearing.

Returning to <FIG>, in one implementation, system <NUM> includes a compression ring <NUM> that is arranged to apply axial compression to the knitted wire mesh pad(s) of bearing damper <NUM>. Compression ring <NUM> is arranged in an annular space between inner support wall <NUM> and bearing housing <NUM>. Compression ring <NUM> can be actuated to travel along bearing housing <NUM>, where the axial travel of compression ring <NUM> results in changes in axial compression applied to the knitted wire mesh pad(s) of bearing damper <NUM>. An outer surface of compression ring <NUM> includes a thread <NUM> that engages a complementary thread <NUM> on an inner surface of bearing housing <NUM>. Compression ring <NUM> travels in an axial direction (that is, along bearing housing <NUM> and inner support wall <NUM>, or in a direction parallel to axial axis <NUM>) as compression ring <NUM> is rotated to adjust the threaded engagement between threads <NUM>, <NUM>.

In one implementation, an anti-rotation ring <NUM> is disposed at the other end surface of bearing damper <NUM> and in between bearing damper <NUM> and compression ring <NUM>. In this position, one end of anti-rotation ring <NUM> abuts bearing damper <NUM>, and the other end of anti-rotation ring <NUM> abuts compression ring <NUM>. Anti-rotation ring <NUM> includes a ring with radially projecting tabs <NUM> on the outer periphery of the ring that fit into respective slots <NUM> in bearing housing <NUM>. Tabs <NUM> can move in an axial direction within slots <NUM>, which allows anti-rotation ring <NUM> to move relative to bearing housing <NUM> in the axial direction. However, movement of tabs <NUM> in the circumferential direction is prevented, which also prevents rotation of the bearing damper <NUM> as the compression ring <NUM> is rotated. Axial travel of compression ring <NUM> will result in axial travel of anti-rotation ring <NUM>, which will result in axial compression of the knitted wire mesh pad(s) in bearing damper <NUM>. In addition to preventing rotation, anti-rotation ring <NUM> allows simple adjustment of the initial axial compression applied to the bearing damper <NUM> (by using a different thickness anti-rotation ring). Also, anti-rotation ring <NUM> ensures uniform distribution of compression stress on bearing damper <NUM> and forms a "sacrificial", easily replaceable low-cost component that protects bearing damper <NUM> from wear as compression ring <NUM> rotates.

<FIG> shows a bearing support arrangement where radial compression or both radial compression and axial compression can be applied to bearing damper <NUM> by axial travel of compression ring <NUM>. In <FIG>, wedge ring <NUM> and mating wedge ring <NUM> are disposed between bearing damper <NUM> and an inner surface of bearing housing <NUM>. Mating wedge ring <NUM>, which is split and sized to allow radial contraction, is disposed between wedge ring <NUM> and an outer wall surface of bearing damper <NUM>. Each wedge ring is a ring having a tapered surface. In the case of wedge ring <NUM>, the tapered surface is on the outer diameter of the ring. In the case of wedge ring <NUM>, the tapered surface is on the inner diameter of the ring. The tapered surfaces of the wedge structures <NUM>, <NUM> are in abutting relation. Wedge ring <NUM> also abuts shoulder 184a in bearing housing <NUM>, while wedge ring <NUM> abuts an inner wall 184b in bearing housing <NUM>. Anti-rotation ring <NUM> abuts wedge ring <NUM> so that axial travel of anti-rotation ring <NUM> results in axial movement of wedge ring <NUM> against wedge ring <NUM>. Axial travel of compression ring <NUM> will result in axial travel of anti-rotation ring <NUM>, which will result in both axial compression of bearing damper <NUM> and radial displacement of wedge ring <NUM>. Radial displacement of wedge ring <NUM> will apply a radial compression to bearing damper <NUM>.

Returning to <FIG> and <FIG>, bearing system <NUM> includes an actuator <NUM> to drive compression ring <NUM> in order to apply axial compression to bearing damper <NUM>. In one implementation, actuator <NUM> includes a worm gear <NUM> that is disposed at one end of compression ring <NUM>. Worm gear <NUM> is coupled to (for example, attached to or integrally formed with) compression ring <NUM> such that rotation of worm gear <NUM> results in rotation of compression ring <NUM>. Actuator <NUM> includes a worm screw (also called worm) <NUM> that is arranged to mesh with worm gear <NUM>. As shown more clearly in <FIG>, worm screw <NUM> may be supported by bearing housing <NUM> in a position to mesh with worm gear <NUM>. As an example, bearing housing <NUM> may include mounts <NUM>, <NUM> to support the shaft of worm screw <NUM>. Mounts <NUM>, <NUM> may include bushings (not shown) to support rotation of the shaft of worm screw <NUM>. Worm gear <NUM> and worm screw <NUM> form a worm drive. Worm screw <NUM> can be rotated in response to measured vibrations in the system. Worm screw <NUM> will rotate worm gear <NUM>, which will result in rotation of compression ring <NUM> (in <FIG> and <FIG>) and travel of compression ring <NUM> in the axial direction. In other implementations, a rotary drive besides a worm drive may be used to rotate compression ring <NUM>.

Referring to <FIG>, <FIG>, <FIG>, and <FIG>, system <NUM> may include one or more vibration sensors to measure vibrations in the system, or vibrations in an environment of the bearing damper. In one example, vibration of shaft <NUM> is measured using one or more vibration sensors <NUM>, which may be, for example, non-contact proximity sensors. Alternatively, or in addition, sensor(s) <NUM> may be arranged on bearing housing <NUM> or structural support <NUM> to measure vibrations. Each vibration sensor <NUM> may be in communication with a controller <NUM>. Controller <NUM> may include a driver to receive the output of vibration sensor <NUM>, memory to store data and computer executable instructions, a processor to execute computer executable instructions, and other controller components not specifically mentioned. System <NUM> may include a motor <NUM> to rotate worm screw <NUM>. In one implementation, motor <NUM> is a rotary motor that drives screw <NUM>. In other implementations, the motor could be a linear motor that drives a rack-and-pinion mechanism. Controller <NUM> may generate control signals for motor <NUM> in response to the output of vibration sensor <NUM>. Motor <NUM> may receive control signals from controller <NUM> and rotate worm screw <NUM> in order to achieve a desired axial compression (and optionally radial compression) of the knitted wire mesh pad(s) in bearing damper <NUM>.

<FIG> shows an example logic of the controller (<NUM> in <FIG> and <FIG>). At <NUM>, vibration data from the vibration sensor(s) (<NUM> in <FIG> and <FIG>) are received. The vibration sensor(s) may send data to the controller on a continuous basis. At <NUM>, the current vibration level is determined from the vibration data. At <NUM>, a rate of change of the vibration level is determined. Suppose that the vibration level at a previous time Ta is Va and the vibration level at a current time Tb > Ta is Vb. Then, the rate of change in vibration level can be expressed as ΔV/ΔT = (Vb - Va) / (Tb - Ta). The initial vibration level before adjustment can be set to V0. At <NUM>, the current vibration level is compared to a vibration level threshold set for the system. If the current vibration level is not greater than the vibration level threshold, then at <NUM>, the controller may determine if the rate of change in vibration level is greater than a rate of change threshold set for the system. If the current vibration level is not greater than the vibration level threshold and the rate of change of vibration level is not greater than the rate of change threshold, the controller may return to <NUM>. If the current vibration level is greater than the vibration level threshold or the rate of change in vibration level is greater than the rate of change threshold, then at <NUM>, the controller adjusts the stiffness and damping of the bearing damper (<NUM> in <FIG> and <FIG>).

<FIG> shows an example logic for adjusting the stiffness and damping of the bearing damper. At <NUM>, an axial compression adjustment (Z) to apply to the bearing damper is set to an adjustment threshold. At <NUM>, the axial compression of the bearing damper is varied by ± Z. That is, if the bearing damper has a current axial length of L, a +Z axial compression adjustment is made (that is, L is decreased by Z) and a -Z axial compression adjustment is made (that is, L is increased by Z). The adjustment is made by moving the compression ring (<NUM> in <FIG> and <FIG>) in a direction towards the bearing support (+Z adjustment) or in a direction away from the bearing support (-Z adjustment). The vibration level (V1) when the +Z axial compression adjustment is applied is determined from the vibration data received after the adjustment. The vibration level (V2) when the -Z axial compression adjustment is applied is also determined from the vibration data received after the adjustment. Depending on the bearing configuration, the axial compression adjustment may result in an axial compression in the bearing damper or both an axial compression and radial compression in the bearing damper. At <NUM>, the bearing damper is held at the axial compression corresponding to the minimum of the vibration levels V0, V1, and V2. The value of V0 is then set to this new current vibration level. At <NUM>, the controller determines if the current vibration level is less than the vibration level threshold set for the system. If the current vibration level is less than the vibration level threshold, then the adjustment of the stiffness and damping of the bearing damper has been completed. Otherwise, at <NUM>, Z is decreased. For example, Z may be reduced by half. Then, at <NUM>, the controller determines if the value of Z is less than the adjustment threshold. If the value of Z equal to or greater than the adjustment threshold, the controller then returns to <NUM> with the updated value of Z to adjust the axial compression of the bearing damper.

Referring to <FIG>, <FIG>, and <FIG>, shaft <NUM> may be fitted in or received in bearing <NUM> of system <NUM>. Shaft <NUM> may be rotated relative to bearing <NUM> and about axial axis <NUM> as part of performing a function in a machine. With the machine running and shaft <NUM> rotating about axial axis <NUM>, vibrations in system <NUM> may be measured using vibration sensor(s) <NUM>. Controller <NUM> may receive vibration data from vibration sensor(s) <NUM> and determine whether to adjust an axial compression of bearing damper <NUM> in order to adjust a stiffness and damping of bearing damper <NUM> and thereby provide stability to rotation of shaft <NUM>. Controller <NUM> may send control signals to actuator <NUM> to move compression ring <NUM> in a manner to apply a predetermined axial compression (and optionally a radial compression) to bearing damper <NUM>. Controller <NUM> may monitor the vibration level in system <NUM> and automatically adjust the axial compression (and optionally a radial compression) of bearing damper <NUM> such that the vibration level within system <NUM> is below a threshold. Controller <NUM> may operate according to the logic shown in <FIG> and <FIG>.

System <NUM> can be incorporated into a machine. When machinery vibration starts to exceed the machine's vibration level or rate-of-change setpoints, system <NUM> can automatically modify the bearing support stiffness and damping to lower the vibration and maintain operation and production without having to shut down the machine. The system tolerates fluids and lubricants in the machine and does not require isolation from them to perform. Moreover, the vibration control is achieved without use of fluids, lubrication, electromagnetic forces, or any auxiliary systems to produce the damping force. System <NUM> provides an automated method of maintaining performance and extending the useful life of the bearing damper through re-compressing of the knitted wire mesh pad(s) in the bearing damper to recover damping. Re-compression of the knitted wire mesh pad(s) can be accomplished while the machine is online.

<FIG> shows one practical application of system <NUM> in a centrifugal pump <NUM>. Centrifugal pump <NUM> contains a rotating impeller <NUM> within a stationary pump casing <NUM>. Shaft <NUM> is connected at one end to impeller <NUM>. The other end of shaft <NUM> includes a coupler <NUM> that can be used to couple shaft <NUM> to a drive motor (not shown). Shaft <NUM> is supported by two sets of bearings - bearing <NUM> that is part of system <NUM> and another bearing <NUM> that is mounted in pump casing <NUM>. Bearings <NUM>, <NUM> are shown as rolling-element bearings. However, any type of bearings may be used with centrifugal pump <NUM>. Bearing housing <NUM> of system <NUM> has been integrated with pump casing <NUM>. The version of system <NUM> shown in <FIG> is the one in <FIG> and <FIG>. However, any of the other versions of system <NUM> shown in <FIG> may be used with centrifugal pump <NUM>. Other details of the centrifugal pump are not described herein since centrifugal pumps are well known.

Claim 1:
A system (<NUM>), comprising:
a bearing housing (<NUM>);
a bearing (<NUM>) disposed within the bearing housing (<NUM>), the bearing (<NUM>) to receive and support rotation of a shaft (<NUM>) about an axial axis (<NUM>);
a bearing damper (<NUM>) disposed around the bearing (<NUM>), the bearing damper (<NUM>) comprising a knitted wire mesh pad (<NUM>) having a length in an axial direction that is parallel the axial axis (<NUM>) and a wall thickness in a radial direction that is transverse to the axial axis (<NUM>);
a compression ring (<NUM>) positioned to be movable relative to the bearing housing (<NUM>) in the axial direction, a movement of the compression ring (<NUM>) in the axial direction to apply a compression to the bearing damper (<NUM>) resulting in a change in at least one of the length and the wall thickness of the knitted wire mesh pad (<NUM>) and a corresponding change in a stiffness and a damping of the bearing damper (<NUM>); and
an actuator (<NUM>) coupled to the compression ring (<NUM>) and controllable to move the compression ring (<NUM>) in the axial direction in response to mechanical vibrations in an environment of the bearing damper (<NUM>);
characterised in that
the actuator (<NUM>) comprises a worm drive.