Dampened link

Abstract

Devices, systems, and methods for damping vibration of a structural component or power-transmission shafts are disclosed. Damping devices, systems, and methods utilize a lightweight damping device, configured to reduce the resonant amplitude of the first several beaming modes and / or torsional modes of bending a hollow shaft or strut. The device is inserted and secured within the original structural component or shaft. When the primary shaft undergoes bending due to modal characteristics, the damping elements react to dissipate energy, which effectively reduces the resonant amplitude.

Description

DAMPENED LINKBACKGROUND

[0001] Structural components, including shafts, struts, and beams, are used in a variety of different applications, for example, in frames or mounts for supporting, equipment or machinery. Individual shafts and / or struts are typically hollow, which allows manufacturers and / or operators to benefit from reductions in cost and / or weight, for example, especially in regards to vehicle (e.g., aircraft, automobile, etc.) systems. Rotating components within the supported machinery (e.g., engines, motors, rotors, propellers, or the like) can impart vibration to the hollow shafts and struts supporting the equipment. In some aspects, this vibration can excite flexural and torsional beaming modes of vibration imparted to individual struts within a frame or mount.

[0002] Conventional methods of reducing vibration within a structural component or power transmission shaft include either designing a component that will have a suitable margin or thickness between the rotating structure and the individual structural component, or providing a tuned mass for altering the tuning of the structural component. Conventional methods are problematic, however, as adding margins and / or tuned masses will increase the weight of the structural component, which is undesirable.

[0003] Thus, the industry would benefit from an improved damping thrust link configuration.SUMMARY

[0004] Disclosed is a dampened link. The dampened link comprises a tubular body having a first end, a second end and an inner surface with a damping device positioned within the tubular body. The damping device comprises: a shaft having a first end and a second end; a first wedge adjustably retained on the shaft proximate to the first end, the first wedge having a first outer surface having a generally convex configuration; a second wedge adjustably retained on the shaft proximate to the second end, the second wedge having a first outer surface having a generally convex configuration; at least two inserts positioned between the first and second wedges, each insert having a first end and a second end, each insert having a first surface configured to engage the inner surface of the tubular body and a second surface configured to receive the shaft, each insert having an internal chamber; a plurality of particles retained within the internal chamber of each insert.

[0005] Also disclosed is a method for preparing a dampened link. The dampened link having tubular body with a first end, a second end and an inner surface. The method comprises the steps of:providing a damping device configured to be positioned within the tubular body, the damping device comprising: a shaft having a first end and a second threaded end, a bolt head carried by the first end and a nut carried by the second threaded end; a first wedge positioned on the shaft proximate to the first end, the first wedge having a first outer generally convex surface; a second wedge positioned on the shaft proximate to the second end, the second wedge having a first outer generally convex surface; the first wedge adjustably retained on the shaft; the second wedge adjustably retained on the shaft; at least two inserts positioned between the first and second wedges, each insert having a first end and a second end, each insert having a first surface configured to engage the inner surface of the tubular body and a second surface configured to receive the shaft, each insert having an internal chamber.Particles having a desired density are added to the internal chamber of each insert. To retain the particles within each internal chamber, the first and second wedges are adjusted to engage the inserts. Subsequently, the damping device is placed within the tubular body and positioned at a desired location within the tubular. Once positioned at the desired location, the distance between the first and second wedges is adjusted to force the first surface of each insert to engage the inner surface of the tubular body with sufficient pressure to retain the damping device at the desired location within the tubular body, thereby providing a dampened link.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 is a perspective view of the thrust link.

[0007] FIG. 2 is a partial sectional view depicting the damping device positioned within the tubular body of the thrust link.

[0008] FIG. 3 is an enlarged view of the partial section view of FIG. 2 focused on the damping device and the engagement of the damping device with the internal walls of the tubular body of the thrust link.

[0009] FIG. 4. depicts one embodiment of the damping device.

[0010] FIG. 5 depicts the wedge elements of the damping device.

[0011] FIG. 6 depicts the wedge elements on the shaft portion of the damping device.

[0012] FIG. 7 is a perspective view of the first end of the shaft portion of the damping device depicting the retaining / adjusting elements of the damping device.

[0013] FIG. 8 is a perspective view of one example of an insert portion of the damping device.

[0014] FIG. 9 is a perspective view depicting the insert portions of a damping device.

[0015] FIG. 10 is a partial sectional view depicting two damping devices positioned within the tubular body of the thrust link.

[0016] FIGS. 11A-D depict the damping response of a thrust link utilizing the damping device disclosed herein.

[0017] FIG. 12 depicts shaft first end having threads with a spring, washer and nut adjustably retaining the first wedge on the shaft of the damping device.

[0018] FIG. 13 depicts shaft second end having threads with a spring, washer and nut adjustably retaining the second wedge on the shaft of the damping device.

[0019] FIG. 14 is an exploded view which also depicts the internal threads of a wedge.DETAILED DESCRIPTION

[0020] The drawings included with this application illustrate certain aspects of the embodiments described herein. However, the drawings should not be viewed as exclusive embodiments. The subject matter disclosed is capable of considerable modifications, alterations, combinations, and equivalents in form and function, as will occur to those skilled in the art with the benefit of this disclosure.

[0021] The present disclosure may be understood more readily by reference to these detailed descriptions. For simplicity and clarity of illustration, where appropriate, reference numerals may be repeated among the different figures to indicate corresponding or analogous elements. The following description is not to be considered as limiting the scope of the embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts may have been exaggerated to better illustrate details and features of the present disclosure. Also, the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting except where indicated as such.

[0022] Throughout this disclosure, the terms “about”, “approximate”, and variations thereof, are used to indicate that a value includes the inherent variation or error for the device, system, or measuring method being employed as recognized by those skilled in the art.

[0023] FIGS. 1 -10 and 12-14 depict exemplary embodiments of a thrust link 10 and a damping device 20 suitable for use within the tubular body 12 of thrust link 10. In addition to thrust links, the present invention will also be applicable to any structural link which needs to be dampened in order to reduce vibrational stress. For simplicity, the remaining discussion will describe the dampening device in terms of thrust links. Thrust links 10 are commonly used in aerospace and other industries which need to react forces between supported components. In the aerospace industry, thrust links 10 are critical structural components necessary to the safe transfer of loads from a supported engine to an airframe. As such thrust links should be designed to have natural frequencies which do not correspond to the vibrational frequenciesinduced by engine operation. Changing engine designs have made this desired goal increasingly difficult. Therefore, incorporation of frequency damping device 20 into the thrust link 10 is desirable.

[0024] Addition of damping device 20 to thrust link 10 provides several advantages. Damping device 20 permits selection of thrust links 10 with natural frequencies within the operational frequencies of supported engines (not shown). As depicted in FIGS. 2 and 3, damping device 20 fits within the tubular body 12 of thrust link 10. Thus, the configuration of damping device 20 does not require additional space in the mounting area of the engine and does not add significantly to the overall weight of the engine support system. Further, by locating damping device 20 to the interior of thrust link 10, damping device 20 provides damping even in the high temperature areas associated with aircraft engine operation, i.e. temperatures in excess of 200°C. More importantly, damping device 20 provides the ability to fine tune the resulting damping effect by permitting relocation of damping device along the interior of tubular body 12.

[0025] Additionally, as discussed in more detail below, the configuration of damping device 20 readily permits removal, inspection and / or modification of damping device 20. While the FIGS, depict damping device 20 with four inserts 50, the number of inserts may be varied depending on the expected operational environment with as few as two or three inserts used. One embodiment of damping device 20 is a particle damper. In this embodiment, inserts 50 have an internal chamber 62 suitable for receiving particles 68 of varying sizes and composition. During inspection of damping device 20, the make-up of particles 68 can be readily altered as desired. Thus, the mass and free space within chamber 62 can be easily modified.

[0026] Turning now to the FIGS, the structure of thrust link 10 and damping device 20 will be described. Thrust link 10 includes a tubular body 12, i.e. a hollow body having an interior chamber with an inner surface 18. Thrust link 10 has a first end 14 and a second end 16. At least one of first and second ends 14, 16 are removably secured to tubular body 12. In the example provided by FIGS. 1 and 2, threads, not shown, secured end 14 to tubular body 12 while a weld, not shown, secures second end 16 to tubular body 12. In most cases, first and second ends 14, 16 provide attachment points or fittings for securement to a supported engine and another structure, not shown. The variety of fittings suitable for use as first and second ends 14, 16 are well known to those skilled in the art and will not be discussed further here. While either end 14 or 16 may be removable, the primary requirement is the ability to access the interior of tubular body 12 for insertion, adjustment, inspection, replacement or modification of damping device 20.

[0027] With reference to FIGS. 2 and 3, damping device 20 is located within and adjustably retained at a desired location within tubular body 12. As discussed in further detail below, location adjustment of damping device 20 within tubular body 12 permits changes in the dampingcharacteristics of damping device 20. Although depicted as centrally located, damping device 20 may be located anywhere within tubular body 12. The ability to select the location of damping device 20 within tubular body 12 provides the ability to select the desired damping modes provided by damping device 20. For example, the first mode response for tubular body 12 will have maximum motion at the center of tubular body 12. As a result, centering of damping device 20 will provide maximum effectiveness in damping this mode. If the components joined by thrust link 10 generate two separate modes of response that require damping, then positioning of damping device 20 closer to first or second end 14, 16 will provide damping of both modes.

[0028] Alternatively, two or more damping devices 20 may be located within tubular body 12. Positioning of two damping devices 20 within tubular body 12 provides the ability to dampen both first and second mode responses of tubular body 12. In this embodiment, one damping device 20 will be centrally located and the second damping device will be located at a predetermined position towards either end of tubular body 12 to provide dampening of second mode vibrations as determined by the specific application of tubular body 12. The actual location of additional damping devices 20 will depend on the length of tubular body 12 and operation of components joined by tubular body 12.

[0029] With reference to FIGS. 3-7, the configuration of damping device 20 includes a shaft 22 having a first end 24 and a second end 26. Shaft 22 supports first and second wedges 28a, 28b with shaft 22 passing through a central hole 29 located in each wedge 28a, 28b. Wedges 28a, 28b are depicted with a first surface 32 having a generally wedge or convex configuration and a second surface 34 in an optional concave configuration. In some embodiments, wedges 28a, 28b may have a generally pyramidal configuration with the point or wedge portion of the pyramid facing inward on shaft 22, i.e. the points of each wedge 28a, 28b are facing each other. Each wedge 28a, 28b has a threaded hole 27 located on the second surface of wedge 28a, 28b. Threaded hole 27 may pass through wedge 28a, 28b; however, threaded hole 28 may alternative extend only partially into wedge 28a, 28b. Threaded hole 27 provides the ability to adjust the position of damping device within tubular body 12. With damping device 20 loosely fitted within tubular body 12 one can secure a rod having a threaded end to damping device 20 by threading the end of the rod into hole 27. Following attachment of the rod to wedge 28a or 28b, adjustment of the location of damping device 20 can be achieved pushing or pulling damping device to the desired location.

[0030] Damping device 20 also includes at least two inserts 50. Inserts 50 have first and second ends 52 and 54. Insert ends 52, 54 have a configuration suitable for engagement by wedges 28a, 28b. In one embodiment, insert ends 52, 54 have a configuration which corresponds to the angle of wedges 28a, 28b. Inserts 52, 54 have an external or outer surface 56 which engages inner surface 18 of tubular body 12. Typically, although not required, insert outer surface56 will have a radius which corresponds to the internal radius of inner surface 18. However, tubular body 12 may have geometric configurations other than round tubulars; therefore, inserts 50 are not limited to curved outer surfaces 56. Regardless of the configuration of the outer surface, outer surfaces 56 will provide sufficient contact surface such that damping device 20 can be selectively retained at the desired location within tubular body 12 through frictional engagement of outer surfaces 56 with inner surface 18 of tubular body 12. Inserts 50 may also have an inner surface or groove 58 suitable for receiving and / or permitting passage of shaft 22. In most embodiments, inner surface or groove 58 provides an unrestricted space for shaft 22 such that shaft 22 may freely rotate between inserts 50.

[0031] With reference to FIGS. 3-4 and 6-7, the adjustment of damping device to provide frictional engagement with inner surface 18 of tubular body 12 will be described. As reflected by the FIGS, several options exist for adjusting the relative positions of wedges 28a, 28b. In general, the configuration of shaft 22, shaft ends 24, 26 and wedges 28a, 28b, provides the ability to adjust the distance between wedges 28a, 28b thereby applying a desired degree of pressure to inserts 50. Application of pressure at insert ends 52, 54 forces inserts 50 apart and into contact with the inner surface 18 of tubular body 12. Adjustment of wedges 28a, 28b provides the pressure necessary to retain damping device 20 at the desired location within tubular body 12. Thus, the pressure applied needs to preclude lateral movement along the length of tubular body 12 under vibratory loading, i.e. during operation of the system using thrust link 10, thereby providing the desired damping by translating movement of particles 68 within inserts 50 to tubular body 12.

[0032] As depicted in FIGS. 6-7, first end 24 terminates in a bolt head 25. Positioned between bolt head 25 and wedge 28a is a first washer 36, a spring 42 and a second washer 38. One option for opposing end 26 of shaft 22 is depicted in FIGS. 13. In this configuration, end 26 carries threads 71 with wedge 28b positioned on shaft 22 followed by a washer 36, spring 42, washer 38 and nut 44. Thus, rotation of either shaft 22, using bolt head 25, or rotation of nut 44 will provide the desired alteration of distance between wedges 28a, 28b. FIG. 12 depicts an alternative embodiment of first end 24. As depicted in FIG. 12, first end 24 carries threads 69. Wedge 28a is positioned on shaft 22 followed by a washer 36, spring 42, washer 38 and nut 44. Thus, adjustment of either nut 44 will provide the desired alteration of distance between wedges 28a, 28b. In the embodiment of FIGS. 6-7 and 13, wedges 28a and 28b do not have internal threads.

[0033] While first and second springs 42 are optional, incorporation of springs 42 provides compensation for different thermal expansion coefficients of particle damping device 20 and tubular body 12. Thus, first and second springs 42 help balance the forces applied to damping device 20. As an added benefit, springs 42 compensate for temperature changes of tubular body 12 during operation of the supported engine. The balancing force applied by springs 42 helps maintain thenecessary engagement pressure between inserts 50 and inner surface 18 to ensure retention of damping device 20 at the desired location. Additionally, the balancing force protects against failure of individual components of damping device 20. When springs 42 are not used, at least one washer 36 will commonly be positioned between nut 44 or bolt head 25 and wedges 28a, 28b. Thus, above described embodiments, nut 44 or bolt head 25 directly or indirectly engages wedges 28a, 28b.

[0034] Adjustment of bolt head 25 and nut 44 determines the pressure applied by springs 42 to wedges 28a, 28b and in turn to inserts 50. As the adjustment of bolt head 25 and nut 44 reduces the distance between washers 36, 38, springs 42 compress and apply greater pressure to wedges 28a, 28b forcing inserts 50 against inner surface 18. In general, the pressure applied to inserts 50 by first and second wedges 28a, 28b, with or without springs 42, should ensure the retention of damping device 20 at the desired location within tubular body 12. Thus, the pressure applied needs to preclude movement under vibratory loading, i.e. during operation of the system using thrust link 10, thereby providing the desired damping by translating movement of particles 68 within inserts 50 to tubular body 12.

[0035] In summary, incorporation of damping device(s) 20 into thrust link 10 entails the following steps: (1) the inserts 50 are prepared for use by adding the desired number of particles 68 to internal chambers 62; (2) wedges 28a, 28b are placed on shaft 22 and retained by a bolt head 25 cooperating with a pair of washers 36, 38 and a spring 42 on first end 24 of shaft 22 and a nut 44, a pair of washers 36, 38 and a spring 42 on second end 26 of shaft 22 (or any of the alternative arrangements detailed herein); (3) inserts 50 are placed along shaft 22 and damping device is placed into tubular body 12; (4) a rod, not shown, having threads on at least one end is threaded into hole 27 in one of wedges 28a, 28b; (5) using the rod, damping device 20 is positioned at the desired location in tubular body 12; (6) while retaining damping device at the desired location, the distance between wedges 28a, 28b is adjusted by rotation of shaft 22 or nuts 44 thereby reducing the distance between wedges 28a, 28b and forcing inserts 50 against inner surface 18 of tubular body 12 with sufficient pressure to retain damping device 20 at the desired location; (7) removal of the rod from threaded hole 27; (8) close both ends of thrust link by securing the desired attachment points at first and second ends 16, 18.

[0036] Continuing with the alternative embodiments for adjusting the distance between wedges 28a, 28b, FIG. 14 depicts end 26 for an embodiment where both wedges 28a, 28b have internal threads 29a. In this embodiment, either end 24 or 26 will carry bolt head 25 and one end 24, 26 will carry right hand threads while the other end 24, 26 will carry left hand threads. Bolt head 25 provides a ready engagement point for a tool to rotate shaft 22 thereby adjusting the distancebetween wedges 28a, 28b. In this embodiment, the end 24, 26 carrying bolt head 25 may optionally include washers 36, 38 and spring 42.

[0037] As another alternative configuration, end 24 carries bolt head 25 with washers 36, 38 and spring 42 located between bolt head 25 and wedge 28a. Wedge 28a does not have internal threads 29a. In this embodiment, opposing end 26 carries threads 71 which engage threads 29a of wedge 28b thereby providing for adjustment of wedge 28b on shaft 22. Thus, rotation of shaft 22 using bolt head 25 shortens or lengthens the position of wedge 28b relative to wedge 28a depending on the direction of rotation.

[0038] Similarly, in another embodiment, end 24 does not carry bolt head 25. In this embodiment, end 24 carries nut 44 with washers 36, 38 and spring 42 located between bolt head 25 and wedge 28a. In this embodiment, end 26 has threads 71 adjustably supporting wedge 28b. Thus, adjustment of the distance between wedges 28a, 28b may be achieved by tightening nut 44 on shaft 22 thereby changing the position of wedge 28a. Optionally, in this embodiment, end 26 may carry a bolt head 25. Thus, depending on the direction of rotation of shaft 22 by engaging bolt head 25 wedge 28b will move closer to wedge 28a or further away. In a further embodiment, each end 24, 26 is threaded and carries nuts 44 optionally with the arrangement of washers and springs discussed above. In addition to the configurations discussed above, each configuration using a nut 44 on either end of shaft 22 may also include the use of backup nuts, not shown, to lock nuts 44 in place on shaft 22. Adjustment of the distance between wedges 28a, 28b will normally occur prior to attachment of ends 14, 16 to tubular body 12.

[0039] As discussed above, the above embodiments may be modified by providing inserts 50 with internal chambers 62 having ports 64 located in one or both ends 52, 54 of inserts 50. In embodiments using inserts 50 with internal chambers 62, particles 68 are housed in chambers 62. Typically, particles 68 will fill between about 15% and about 40% of the available volume within chambers 62. More typically, about 20% to about 25% of the available volume will be occupied by particles 68. Thus, the embodiments with chambers provide a damping device 20 having the characteristics of a particle damper. The nature of the particles will generally determine the size requirements of chambers 62. For example, particles having greater material density may permit use of smaller chambers 62. Ports 64 may optionally be closed by a plug, not shown. In general, wedges 28a or 28b will block the loss of particles 68 from chambers 62.

[0040] For improved clarity, the following summarizes some of the various optional embodiments and configurations of shaft 22 and wedges 28a, 28b. (1) In one instance, shaft 22 may carry a bolt head 25 at one end 24 and threads on end 26. In this first configuration, when bolt head 25 is present, wedge 28a may free float on shaft 22 proximate to bolt head 25 with optional washers 36, 38 and spring 42 located between wedge 28a and bolt head 25. When threads 71 arepresent on end 26, wedge 28b may include threads 29a in central hole 29 thereby allowing wedge 28b to engage threads 71 and move along shaft 22 when shaft 22 is rotated. When threads 29a are present, nut 44 may be optionally used on end 26. When nut 44 is present, optional washers 36, 38 and spring 42 may be located between wedge 28b and nut 44. However, if wedge 28b omits threads 29a, then nut 44 will be present and may optionally include washers 36, 38 and spring 42 located between wedge 28b and nut 44. Adjustment of the distance between wedges 28a, 28b can be achieved by rotating bolt head 25 while optionally holding nut 44 or the reverse thereof. Alternatively, when wedge 28b carries threads 29, adjustment can be achieved by rotating bolt head 25 to adjust the relative position of wedge 28b to wedge 28a. (2) Alternatively shaft 22 may carry threads on each end 24 and 26. In this embodiment, each end 24, 26 will carry threads 69, 71. In this embodiment either one or both wedges 28a, 28b may carry internal threads 29a which engage threads 69, 71 such that rotation of shaft 22 adjusts the relative positions of wedges 28a, 28b. Alternatively, either or both wedges 28a, 28b may lack internal threads 29a and free float on shaft 22. When wedges 28a, 28b free float, nuts 44 will be present on each end 24, 26. Washers 36, 38 and spring 42 are optionally located on end 24 between nut 44 and wedge 28a. Likewise, washers 36, 38 and spring 42 are optionally located on end 26 between nut 44 and wedge 28b. Adjustment of the relative distance between wedges 28a, 28b can be achieved by adjustment of either nut 44. Generally, in all embodiments which utilize washers 36, 38 and spring 42, spring 42 will be located between washers 36, 38. Finally, an additional nut 44 may be added to either or both ends 24, 26 to abut and lock into place first nut 44.

[0041] The damping effect provided by damping device 20 can be estimated as a function of frequency and acceleration level. Charts, such as depicted in FIGS. 11A-D, provide plots of the typically expected damping ratio for different excitation frequencies and as a function of peak acceleration for a given modal mass ratio between thrust link 10 and damping device 20. The location of damping device 20 within tubular body 12 will be that location which corresponds to the maximum movement amplitude for a given normal vibration mode. By locating damping device 20 at this desired location, the effectiveness of damping device 20 is increased.

[0042] In some instances, the system which incorporates thrust link 10 will require damping of first and second mode vibrations. Under these conditions, one may elect to use two damping devices 20 as depicted in FIG. 10. One damping device 20 will be positioned at the location of the maximum movement amplitude of the first mode and the second damping device positioned at the location of the second movement amplitude, i.e. the second mode of vibration. However, use of two damping devices 20 may not always be practical. Under such conditions, positioning damping device 20 will be selected for primary damping of either the first or second mode. If damping of the first mode is desired, then damping device 20 will be located in the middle of tubular body 12;however, if clamping of the second mode is desired then damping device will be positioned closer to either end at a location determined to provide maximum damping of the second mode.

[0043] When damping device 20 is a particle damper, changes in the modal mass ratio will alter the damping properties of the damping device 20. Higher modal mass ratios will produce a proportionally higher damping effect. One manner of increasing the modal mass ratio will be by selectively positioning damping device 20 at the location, for the given tubular body 12, that the displacement for the mode of interest is highest. For example, for a defined total mass of the particles, the use of materials with different density influences the internal size of the chamber and, as a consequence, the total weight of the enclosure. The use of steel, or tungsten carbide particles would require a smaller chamber and a lighter enclosure. The extreme hardness of tungsten carbide particles is also beneficial to the high resistance to wear, impacts and the durability of the particle damper. Thus, particles 68 will typically have a hardness rating of 7.0 to 10 Mohs. More typically, a hardness value of 7.5 to 9.0 Mohs will be sufficient. Thus, the steps of selecting the desired modal mass ratio of damping device 20 and locating the damping device 20 at the location of the maximum movement amplitude of the first mode will effectively dampen vibrations experienced by tubular body 12. Further, damping of vibrations can be achieved by locating additional damping devices 20 in tubular body 12 at the locations of second and third vibration modes.

[0044] Other embodiments of the present invention will be apparent to one skilled in the art. For example, the specific geometric configurations discussed above for the design of wedges 28a, 28b are not limiting. Rather, any geometric configuration capable engaging and applying the pressure necessary to force inserts 50 against interior surface 18 to retain damping device 20 at the desired location within tubular body 12 will be suitable for use. Further, multiple damping devices 20 may be located within tubular body 12 to account for a variety of conditions. As such, the foregoing description merely enables and describes the general uses and methods of the present invention. Accordingly, the following claims define the true scope of the present invention.

Claims

What is claimed Is:

1. A dampened link (10) comprising: a tubular body (12) having a first end (14), a second end (16) and an inner surface (18); a damping device (20) positioned within the tubular body, the damping device comprising: a shaft (22) having a first end (24) and a second end (26); a first wedge (28a) adjustably retained on the shaft proximate to the first end, the first wedge having a first outer surface having a generally convex configuration (32); a second wedge (28b) adjustably retained on the shaft proximate to the second end, the second wedge having a first outer surface having a generally convex configuration (32); at least two inserts (50) positioned between the first and second wedges, each insert having a first end (52) and a second end (54), each insert having a first surface (56) configured to engage the inner surface of the tubular body and a second surface (58) configured to receive the shaft, each insert having an internal chamber (62); a plurality of particles (68) retained within the internal chamber of each insert.

2. The dampened link of claim 1 , wherein the first end of each insert has a slope which corresponds to the slope of the outer generally convex surface of the first wedge and the second end of each insert has a slope which corresponds to the slope of the outer generally convex surface of the second wedge.

3. The dampened link of claim 1 , wherein each insert has a port located on either the first end or the second end and wherein in the assembled configuration of the dampened link, the outer generally convex surface of either the first wedge or the second wedge covers the port.

4. The dampened link of claim 1 , having at least four inserts positioned between the first and second wedges.

5. The dampened link of claim 1 , wherein at least one of the first end or the second end of the tubular body is removably secured to the tubular body and the damping device is adjustably and removably positioned within the tubular body.

6. The dampened link of claim 1, wherein the configuration of damping device provides for frictional engagement between the inner surface of the tubular body and the first surface of each insert, wherein the frictional engagement retains the damping device at the desired location within the tubular body.

7. The dampened link of claim 1 , further comprising a second damping device positioned within the tubular body.

8. The dampened link of claim 1 , wherein each wedge has a central opening with the shaft passing through the central opening and second surface opposite of the first outer surface having a generally convex configuration and a threaded hole positioned in the second surface.

9. The dampened link of claim 8, wherein the threaded hole passes from the second surface to the first outer surface.

10. The dampened link of claim 1 , wherein the first end of the shaft carries a bolt head and the second end of the shaft carries external threads and a nut.11 . The dampened link of claim 1 , wherein the first end of the shaft carries external threads and a nut and the second end of the shaft carries external threads and a nut.

12. The dampened link of claim 1, wherein the first end of the shaft carries a bolt head and a first spring, wherein the first spring is positioned between the first wedge and the bolt head and the second end of the shaft carries external threads, a nut and a second spring, wherein the second spring is positioned between the second wedge and the nut.

13. The dampened link of claim 1 , wherein the first end of the shaft carries external threads, a first nut and a first spring, wherein the first spring is positioned between the first wedge and the first nut and the second end of the shaft carries external threads, a second nut and a second spring, wherein the second spring is positioned between the second wedge and the second nut.

14. The dampened link of claim 1 , wherein a change in distance between the first and second wedges changes the frictional engagement of the outer surface of each insert with the inner surface of the tubular body.

15. The dampened link of claim 1 , wherein a reduction in distance between the first and second wedges increases the frictional engagement of the outer surface of each insert with the inner surface of the tubular body.

16. The dampened link of claim 1 , wherein the particles fill between about 15% to about 40% of the internal chamber of each insert.

17. The dampened link of claim 1 , wherein the first end of the shaft carries a bolt head and the second end of the shaft carries external threads, and the second wedge has a central opening with internal threads which engage the external threads of the second end of the shaft, wherein rotation of the shaft alters the distance between the first wedge and the second wedge.

18. A damping device (20) configured to be positioned within a tubular body, the tubular body having an inner surface, the damping device comprising: a shaft (22) having a first end (24) and a second end (26); a first wedge (28a) adjustably retained on the shaft proximate to the first end, the first wedge having a first outer surface having a generally convex configuration (32); a second wedge (28b) adjustably retained on the shaft proximate to the second end, the second wedge having a first outer surface having a generally convex configuration (32); at least two inserts (50) positioned between the first and second wedges, each insert having a first end (52) and a second end (54), each insert having a first surface (56)configured to engage the inner surface of the tubular body and a second surface (58) configured to receive the shaft, each insert having an internal chamber (62); a plurality of particles (68) retained within the internal chamber of each insert.

19. The damping device of claim 18, wherein the first end of each insert has a slope which corresponds to the slope of the outer generally convex surface of the first wedge and the second end of each insert has a slope which corresponds to the slope of the outer generally convex surface of the second wedge.

20. The damping device of claim 18, wherein each insert has a port located on either the first end or the second end and wherein in the assembled configuration of the dampened link, the outer generally convex surface of either the first wedge or the second wedge covers the port.

21. The damping device of claim 18, wherein the configuration of damping device provides for frictional engagement between the inner surface of the tubular body and the first surface of each insert, wherein the frictional engagement retains the damping device at the desired location within the tubular body.

22. The damping device of claim 18, wherein the first end of the shaft carries a bolt head and the second end of the shaft carries external threads and a nut.

23. The damping device of claim 18, wherein the first end of the shaft carries external threads and a nut and the second end of the shaft carries external threads and a nut.

24. The damping device of claim 18, wherein the first end of the shaft carries a bolt head and a first spring, wherein the first spring is positioned between the first wedge and the bolt head and the second end of the shaft carries external threads, a nut and a second spring, wherein the second spring is positioned between the second wedge and the nut.

25. The damping device of claim 18, wherein the first end of the shaft carries external threads, a first nut and a first spring, wherein the first spring is positioned between the first wedge and the first nut and the second end of the shaft carries external threads, a second nut and a second spring, wherein the second spring is positioned between the second wedge and the second nut.

26. The damping device of claim 18, wherein a change in distance between the first and second wedges changes the frictional engagement of the outer surface of each insert with the inner surface of the tubular body.

27. The damping device of claim 18, wherein a reduction in distance between the first and second wedges increases the frictional engagement of the outer surface of each insert with the inner surface of the tubular body.

28. The damping device of claim 18, wherein the particles fill between about 15% to about 40% of the internal chamber of each insert.

29. The damping device of claim 18, wherein the first end of the shaft carries a bolt head and the second end of the shaft carries external threads, and the second wedge has a central opening with internal threads which engage the external threads of the second end of the shaft, wherein rotation of the shaft alters the distance between the first wedge and the second wedge.

30. A dampened link (10) comprising: a tubular body (12) having a first end (14), a second end (16) and an inner surface (18); a damping device (20) positioned within the tubular body, the damping device comprising: a shaft (22) having a first end (24) and a second threaded end (26), a bolt head (25) carried by the first end and a nut carried by the second threaded end; a first wedge (28a) positioned on the shaft proximate to the first end, the first wedge having a first outer generally convex surface (32); a second wedge (28b) positioned on the shaft proximate to the second end, the second wedge having a first outer generally convex surface (32); the first wedge adjustably retained on the shaft; the second wedge adjustably retained on the shaft; at least two inserts (50) positioned between the first and second wedges, each insert having a first end (52) and a second end (54), each insert having a first surface (56) configured to engage the inner surface of the tubular body and a second surface (58) configured to receive the shaft, each insert having an internal chamber (62); a plurality of particles (68) retained within the internal chamber of each insert.31 . A method for preparing a dampened link, the dampened link having tubular body (12) with a first end (14), a second end (16) and an inner surface (18), the method comprising the steps of: providing a damping device configured to be positioned within the tubular body, the damping device comprising: a shaft (22) having a first end (24) and a second threaded end (26), a bolt head (25) carried by the first end and a nut carried by the second threaded end; a first wedge (28a) positioned on the shaft proximate to the first end, the first wedge having a first outer generally convex surface (32); a second wedge (28b) positioned on the shaft proximate to the second end, the second wedge having a first outer generally convex surface (32); the first wedge adjustably retained on the shaft; the second wedge adjustably retained on the shaft; at least two inserts (50) positioned between the first and second wedges, each insert having a first end (52) and a second end (54), each insert having a first surface (56) configured to engage the inner surface of the tubular body and asecond surface (58) configured to receive the shaft, each insert having an internal chamber (62); adding a plurality of particles (68) to the internal chamber of each insert; adjusting the first and second wedges to engage the inserts, thereby retaining the plurality of particles in the internal chamber of each insert; placing the damping device within the tubular body; positioning the damping device at a desired location within the tubular body; adjusting the distance between the first and second wedges thereby forcing the first surface of each insert to engage the inner surface of the tubular body with sufficient pressure to retain the damping device at the desired location within the tubular body, thereby providing a dampened link.

32. The method of claim 31 , wherein the tubular body has first mode vibrations and wherein the desired location of the damping device within the tubular body corresponds to the location of the first mode vibrations of the tubular body.

33. The method of claim 31 , wherein the tubular body has first and second mode vibrations and further comprising placing two damping devices within the tubular body, wherein the first damping device is located at a location corresponding to the first mode of vibration of the tubular body and the second damping device is located at a location corresponding to the second mode of vibration of the tubular body.

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