Patent Publication Number: US-2022226912-A1

Title: Tool holder having anti-vibration arrangement and cutting tool provided with tool holder

Description:
FIELD OF THE INVENTION 
     The subject matter of the present application relates to tool holders, in general, and to such tool holders having an anti-vibration arrangement, in particular, and to such an anti-vibration arrangement having at least three resilient suspension members further in particular. 
     BACKGROUND OF THE INVENTION 
     Tool holders can be provided with an anti-vibration arrangement for suppressing vibration of the tool holder during metal cutting operations. Typically, the anti-vibration arrangement is a spring-mass system that includes a cavity and a vibration absorbing mass suspended therein by elastic supporting members. The cavity can be filled with a viscous fluid. 
     In some such anti-vibration arrangements, said elastic supporting members can be formed from annular type structures (i.e. o-rings). Examples of such tool holding systems, are disclosed in, for example, U.S. Pat. No. 9,579,730, US 2016/305503, U.S. Pat. Nos. 7,234,379, 6,443,673 and 3,774,730. 
     In other such anti-vibration arrangements, said elastic supporting members can be formed from spherical elastic bodies. An example of such tool holding systems is described in JP2008100332A which discloses an anti-vibration tool having a weight elastically supported in a hollow part in a tool body by two substantially spherical elastic bodies. The center part of the weight and the tool body is formed into a conical recess so that the end surface of the tool body and the weight contacting the spherical elastic body easily coincides with the axial center of the weight and the tool body. 
     It is an object of the subject matter of the present application to provide a new and improved anti-vibration arrangement. 
     SUMMARY OF THE INVENTION 
     In accordance with a first aspect of the subject matter of the present application there is provided a tool holder, elongated along a holder longitudinal axis thereof and comprising: 
     a mass housing portion; and 
     an anti-vibration arrangement comprising:
         an interior holder cavity formed in the mass housing portion and having an inwardly facing cavity wall surface;   a vibration absorbing mass having a mass central axis and comprising two axially opposite mass ends and at least three mass recesses; and   at least three non-torus shaped, resilient suspension members, each suspension member being partially located in a respective mass recess and protruding outwardly therefrom, wherein:
           the tool holder is adjustable between an unassembled state and an assembled state, and in the assembled state:
               the vibration absorbing mass is disposed in the interior holder cavity and is elastically suspended therein by the at least three suspension members contacting the inwardly facing cavity wall surface, and thereby forming an oscillating space located between the vibration absorbing mass and the inwardly facing cavity wall surface.   
               
               

     In accordance with a second aspect of the subject matter of the present application there is provided a cutting tool comprising: 
     a tool holder of the type described above; and 
     a cutting portion comprising at least one cutting insert. 
     It is understood that the above-said is a summary, and that features described hereinafter may be applicable in any combination to the subject matter of the present application, for example, any of the following features may be applicable to the tool holder or the cutting tool: 
     The at least three suspension members can be under compressive elastic deformation by contact against the inwardly facing cavity wall surface and the respective mass recess. 
     The at least three suspension members can be formed from a material different from that of the vibration absorbing mass. 
     In the unassembled state, the vibration absorbing mass can be disposed outside the interior holder cavity. Each of the at least three suspension members can be releasably retained in a respective one of the at least three mass recesses of the vibration absorbing mass, by the respective suspension member being under compressive elastic deformation by contact against only a mass recess peripheral surface of the respective one of the at least three mass recesses. 
     Each of the at least three suspension members can have a spherical shape defined by a suspension member radius. 
     The vibration absorbing mass can be elongated along the mass central axis. 
     In the assembled state of the tool holder, the mass central axis can parallel to the holder longitudinal axis. 
     The mass central axis can be co-incident with the holder longitudinal axis. 
     The vibration absorbing mass can have a constant cross-sectional area in a plane oriented perpendicular to the mass central axis. 
     In an end view of the vibration absorbing mass, each mass recess can subtend a mass recess angle from the mass central axis. For any given mass end having two or more mass recesses, the mass recesses can be equally angularly spaced apart from one another about the mass central axis by a recess separation angle. The recess separation angle can be less than the mass recess angle. 
     The at least three mass recesses can be formed at the two opposite mass ends, at least one mass recess being formed at each mass end. 
     The vibration absorbing mass can comprise two mass end surfaces and a mass peripheral surface extending therebetween about the mass central axis, the two mass end surfaces and the mass peripheral surface intersecting to form two mass edges. Each of the at least three mass recesses can be formed at least partially in one of the two mass end surfaces. 
     Each of the at least three mass recesses can be formed partially in one of the two mass end surfaces and partially in the mass peripheral surface so as to intersect one of the two mass edges. 
     Each mass end surface can be rotationally symmetrical about the mass central axis. 
     The two mass end surfaces can be identical. 
     The two mass end surfaces can be rotationally offset from one another about the mass central axis by a rotation angle. 
     For any mass end having two or more mass recesses, the mass recesses can be equally angularly offset about the mass central axis by an offset angle. The rotation angle can be equal to half the offset angle. 
     Each suspension member can protrude outwardly from the respective mass recess in both a radial direction and an axial direction, with respect to the mass central axis. 
     The mass peripheral surface distal the mass end surfaces can have a cylindrical shape defined by a mass radius. 
     The at least three suspension members can have a spherical shape defined by a suspension member radius. The mass radius can be between three to four times the size of the suspension member radius. 
     The two mass end surfaces can be planar and oriented transversely to the mass central axis. 
     For any mass end having two or more mass recesses, the mass recesses can be angularly offset from one another about the mass central axis. 
     The mass recesses can be equally angularly offset from one another about the mass central axis by an offset angle. 
     The cavity wall surface can comprise two opposite cavity wall end surfaces and a cavity wall peripheral surface extending therebetween, the cavity wall peripheral surface extending about the cavity central axis. In the assembled position of the tool holder, each suspension member can abut the cavity wall peripheral surface and one of the two planar cavity wall end surfaces simultaneously. 
     The two cavity wall end surface can be planar. 
     The vibration absorbing mass can comprise an equal number of N mass recesses at each mass end. 
     N can equal 6. 
     The at least three mass recesses can be formed at the two opposite mass ends ( 60 ). The anti-vibration arrangement can comprise a tuning member which can be displaceable along the cavity central axis and which can abut the suspension members at one of the mass ends. 
     The tuning member can comprise a planar tuning abutment surface. The tuning abutment surface can abut said suspension members at said one of the mass ends. 
     The oscillating space can be devoid of a viscous fluid. 
     The mass housing portion can comprise a first metallic material. The vibration absorbing mass can comprise a second metallic material. The second metallic material can be denser than the first metallic material. 
     The cutting portion can be releasably attached to the tool holder. 
     The anti-vibration arrangement can be disposed at a forward end of the cutting tool. 
     The cutting tool can be a rotary cutting tool, designed to rotate about a rotational axis. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       For a better understanding of the present application and to show how the same may be carried out in practice, reference will now be made to the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a cutting tool in accordance with the present application, showing an anti-vibration arrangement; 
         FIG. 2  is an exploded perspective view of a tool holder in  FIG. 1 , in accordance with the present application; 
         FIG. 3  is an axial cross-sectional view of the tool holder in  FIG. 2 ; 
         FIG. 4  is a radial cross-sectional view of the tool holder in  FIG. 2  taken along line Iv-Iv in  FIG. 3 ; 
         FIG. 5  is a perspective view of the anti-vibration arrangement in  FIG. 2 ; 
         FIG. 6  is an exploded perspective view of parts of the anti-vibration arrangement in  FIG. 1 ; 
         FIG. 7  is a side view of the parts of the anti-vibration arrangement in  FIG. 5 ; 
         FIG. 8  is an end view of the parts of the anti-vibration arrangement in  FIG. 5 ; and 
         FIG. 9  is a radial cross-sectional view of the parts of the anti-vibration arrangement in  FIG. 5 , taken along line IX-IX in  FIG. 7 . 
     
    
    
     It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity, or several physical components may be included in one functional block or element. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements. 
     DETAILED DESCRIPTION OF THE INVENTION 
     In the following description, various aspects of the subject matter of the present application will be described. For purposes of explanation, specific configurations and details are set forth in sufficient detail to provide a thorough understanding of the subject matter of the present application. However, it will also be apparent to one skilled in the art that the subject matter of the present application can be practiced without the specific configurations and details presented herein. 
     Attention is first drawn to  FIG. 1  showing a cutting tool  20 , for chip removal, depicting an aspect of the present application. The cutting tool  20  has a tool longitudinal axis A. In accordance with some embodiments of the subject matter of the present application, the cutting tool  20  can be rotary cutting tool. That is to say, the cutting tool  20  is designed to rotate about a rotational axis. In this non-limiting example shown in the drawings, the cutting tool  20  is a milling tool. However, the subject matter of the present application is not restricted only to milling tools and could also be applicable to, for example but not limited to, a drilling tools. The subject matter of the present application may also be applicable to non-rotary cutting tools, such as boring bars. For such non-rotary cutting tools, the cutting tool  20  is not designed to be rotatable in a direction of rotation about the tool longitudinal axis A. 
     The cutting tool  20  includes a tool holder  22 . The cutting tool  20  also includes a cutting portion  24  that includes at least one cutting insert  26 . The at least one cutting insert  26  is designed to perform metal cutting operations and has a cutting edge for that purpose. In accordance with some embodiments of the subject matter of the present application, the at least one cutting insert  26  can be releasably attached to the cutting portion  24 . The cutting portion  24  can be integrally formed with the tool holder  22 . Alternatively, the cutting portion  24  can be releasably attached to the tool holder  22 . The cutting portion  24  can be disposed at a forward end of the tool holder  22 . 
     Reference is now made to  FIG. 2 , showing the tool holder  22 , depicting another aspect of the present application. The tool holder  22  has a holder longitudinal axis B, that defines opposite forward and rear directions D F , D R . The tool holder  22  is elongated along the holder longitudinal axis B. In accordance with some embodiments of the subject matter of the present application, the cutting tool  20  and the tool holder  22  can be co-axial with each other. It should be noted that two elements (e.g. the cutting tool  20  and the tool holder  22  in the present case) are co-axial with each other when their longitudinal axes are co-incident (aligned with other). 
     It should further be noted that use of the terms “forward” and “rearward” throughout the description and claims refer to a relative position in a direction of the holder longitudinal axis B towards the left and right, respectively, in  FIG. 3 . Generally speaking, the forward direction is the direction towards the cutting portion  26 . 
     In accordance with some embodiments of the subject matter of the present application, the tool holder  22  can include two opposite holder end surfaces  30  and a holder peripheral surface  32  that extends therebetween. The holder peripheral surface  32  can extend about the holder longitudinal axis B. 
     The tool holder  22  includes a mass housing portion  40  and an anti-vibration arrangement  34 . The tool anti-vibration arrangement  34  is designed to reduce or eliminate vibration of the cutting tool  20  when the cutting tool  20  performs a metal cutting operation. In accordance with some embodiments of the subject matter of the present application, the anti-vibration arrangement  34  can be disposed at a forward end of the cutting tool  20 . 
     The anti-vibration arrangement  34  includes an interior holder cavity  36  that is formed in the mass housing portion  40 . That is to say, the interior holder cavity  36  is enclosed within the mass housing portion  40 . The holder cavity  36  is formed by an inwardly facing cavity wall surface  38 . The cavity wall surface  38  delimits the holder cavity  36  from the mass housing portion  40 . The mass housing portion  40  surrounds the holder cavity  36 . The holder cavity  36  has a cavity central axis D. In accordance with some embodiments of the subject matter of the present application, the holder cavity  36  can be elongated along a cavity central axis D. The holder cavity  36  can be elongated in the same direction as the tool holder  22 . In particular, the holder cavity  36  can be co-axial with the tool holder  22 . The cavity wall surface  38  can include two opposite cavity wall end surfaces  42  and a cavity wall peripheral surface  44  that extends therebetween. The cavity wall peripheral surface  44  can extend about the cavity central axis D. 
     Referring in addition to  FIG. 3 , showing an axial cross-sectional view of the holder cavity  36  (taken in a plane containing the cavity central axis D) through the cavity wall peripheral surface  44 , the holder cavity  36  has a cavity transverse cross-section. In accordance with some embodiments of the subject matter of the present application, said cavity transverse cross-section can be uniform along the cavity central axis D. The cavity wall peripheral surface  44  can have a generally cylindrical shape. The cavity wall peripheral surface  44  can have a cylindrical shape in the vicinity of the two cavity wall end surface  42  (where the cavity wall peripheral surface  44  abuts a suspension member  62  as described later in the description). The two cavity wall end surfaces  42  can be planar and oriented transversely to the cavity central axis D. The two cavity wall end surfaces  42  can be oriented perpendicular to the cavity central axis D. 
     Reverting to  FIGS. 1 and 2 , the anti-vibration arrangement  34  also includes a vibration absorbing mass  54 . In accordance with some embodiments of the subject matter of the present application, the vibration absorbing mass  54  can be rigid. In some embodiments, while the mass housing portion  40  is formed from a first metallic material such as steel, the vibration absorbing mass  54  may be formed from a denser second metallic material, such as tungsten. 
     Referring to  FIGS. 4-7 , the vibration absorbing mass  54  has a mass central axis E. The vibration absorbing mass  54  includes two axially opposite mass ends  60 . The two axially opposite mass ends  60  are spaced apart from one another along the mass central axis E. In accordance with some embodiments of the subject matter of the present application, the vibration absorbing mass  54  can include two opposite mass end surfaces  56  and a mass peripheral surface  58  that extends therebetween. The mass peripheral surface  58  can extend about the mass central axis E. The two mass end surfaces  56  are located at the two mass ends  60 , respectively. The two mass end surfaces  56  and the mass peripheral surface  58  can intersect to form two mass edges  61 . The vibration absorbing mass  54  can be elongated along the mass central axis E. The vibration absorbing mass  54  can have a generally constant cross-sectional area in a plane oriented perpendicular to the mass central axis E. 
     Referring to  FIGS. 2 and 5-7 , the vibration absorbing mass  54  includes at least three mass recesses  64 . Each mass recesses  64  is recessed in the vibration absorbing mass  54 . The at least three mass recesses  64  are designed to receive a suspension member as described later in the description. Each mass recess  64  is defined by a mass recess peripheral surface  66 . In accordance with some embodiments of the subject matter of the present application, the at least three mass recesses  64  can be identical. The at least three mass recesses  64  can be concavities. The at least three mass recesses  64  can have a partially spherical basic shape. That is to say, each mass recess peripheral surface  66  can lie substantially on an imaginary sphere, facing inwards towards the center of said imaginary sphere. 
     As best seen in  FIG. 6 , in accordance with some embodiments of the subject matter of the present application, the at least three mass recesses  64  can be formed at the two opposite mass ends  60 , with at least one mass recess  64  formed at each mass end  60 . Each of the at least three mass recesses  64  can be formed at least partially in the two mass end surfaces  56 . In particular, each of the at least three mass recesses  64  can be disposed at the periphery of the vibration absorbing mass  54 . Each of the at least three mass recesses  64  can be formed partially in one of the two mass end surfaces  56  and partially in the mass peripheral surface  58  so as to intersect one of the two mass edges  61 . None of the at least three mass recesses  64  may be intersected by the mass central axis E. It is noted that the at least three mass recesses  64  are not annular recesses, extending about the entire 360° circumference extent of the cavity central axis D. Thus, they are not suitable for receiving o-rings. 
     Referring to  FIG. 8 , for any mass end  60  having two or more mass recesses  64 , the mass recesses  64  can be angularly offset from one another about the mass central axis E. The mass recesses  64  can be equally angularly offset from one another about the mass central axis E by an offset angle γ. Such a configuration provides a stable elastic suspension of the vibration absorbing mass  54  within the interior holder cavity  36 . In an end view of the vibration absorbing mass  54 , for any given mass end  60  having two or more mass recesses  64 , the mass recesses  64  can be equally angularly spaced apart from one another about the mass central axis E by a recess separation angle θ. 
     In accordance with some embodiments of the subject matter of the present application, the vibration absorbing mass  54  can include an equal number of N mass recesses  64  at each mass end  60  (N being greater than one) thereby forming a total of 2*N mass recesses  64  in the vibration absorbing mass  54 . In the non-limiting example shown in the drawings, N can be equal to six (that is to say, there is a total of twelve mass recesses  64 , six at each end mass end  60 ). 
     Referring to  FIG. 7 , in accordance with some embodiments of the subject matter of the present application, the mass end surfaces  56  can be planar and oriented perpendicular to the mass central axis E. Referring to  FIG. 8 , the mass peripheral surface  58  distal the mass end surfaces  56  can have a cylindrical shape defined by a mass radius R 2 . Each mass end surface  56  (including any mass recesses  64  located thereat) can be rotationally symmetrical about the mass central axis E. The two mass end surfaces  56  can be identical. The two mass end surfaces  56  can be rotationally offset from one another about the mass central axis E by a rotation angle α. The rotation angle α can be equal to half the offset angle γ. Stated differently, in a view along the mass central axis E, for any given adjacent pair of mass recesses  64  at a given mass end surface  56 , a mass recess  64  at the opposite mass end surface  56  is located exactly angularly halfway between said given adjacent pair of mass recesses  64 . Making reference to  FIG. 8 , in an end view of the vibration absorbing mass  54 , each mass recess  64  subtends a mass recess angle β from the mass central axis E. The mass recess angle β is defined by the angular extremities of the mass recess  64  about the mass central axis E. The recess separation angle θ can be less than the mass recess angle β. 
     In accordance with some embodiments of the subject matter of the present application, the cavity wall peripheral surface  44  can have a shape that matches the shape of the mass peripheral surface  58 . One or both of the two cavity wall end surfaces  42  can have a shape that matches the shape of the corresponding mass end surface  56 . Thus, the holder cavity  36  can have a shape that matches the shape of the vibration absorbing mass  54 . 
     The anti-vibration arrangement  34  includes at least three resilient suspension members  62 . Each suspension member  62  is defined by a suspension member peripheral surface  63 . The at least three suspension members  62  are elastically deformable. In accordance with some embodiments of the subject matter of the present application, the number of suspension members  62  can match the number of mass recesses  64 . The at least three suspension members  62  can be formed from a material different from that of the vibration absorbing mass  54 . In some embodiments, the suspension members  62  are made of rubber, having a Durometer hardness of between 60 A to 95 A. 
     The at least three suspension members  62  are non-torus shaped (i.e. non-annular). That is to say, the at least three suspension members  62  are not be o-rings. In accordance with some embodiments of the subject matter of the present application, generally speaking, the at least three suspension members  62  can have a shape that corresponds to the shape of the at least three mass recesses  64 . The at least three suspension members  62  can be balls. The at least three suspension members  62  can have a spherical shape (i.e. balls). That is to say, each suspension peripheral surface member  63  can lie on an imaginary sphere, facing outwards from the center of said imaginary sphere. Referring to  FIGS. 8 and 9 , each suspension member  62  can be defined by a suspension member radius R 1 . The mass radius R 2  can be between three to four times the size of the suspension member radius R 1 . Stated differently, the mass radius R 2  can be between 300% and 400% the magnitude of the suspension member radius R 1 . Preferably, the mass radius R 2  can be between 325% and 375% the magnitude of the suspension member radius R 1 . The at least three suspension members  62  can be solid. That is to say, the at least three suspension members  62  are not hollow. The at least three suspension members  62  are not fluid. 
     The tool holder  22  is adjustable between an unassembled state and an assembled state. In the unassembled state of the tool holder  22 , the vibration absorbing mass  54  is disposed outside the interior holder cavity  36 . In accordance with some embodiments of the subject matter of the present application, each of the at least three suspension members  62  can be releasably retained in a respective one of the at least three mass recesses  64  of the vibration absorbing mass  54 , by each respective suspension member  62  being under compressive elastic deformation by contact against only the mass recess peripheral surface  66  of the respective one of the at least three mass recesses  64 . For example, each suspension member  62  can be squeezed into a respective mass recess  64  so that the suspension member peripheral surface  63  is urged against and abuts the mass recess peripheral surface  66 . 
     In accordance with some embodiments of the subject matter of the present application, the tool holder  22  includes a cavity axial sealing member  67  which defines the holder cavity  36  in the forward direction D F , and which seals the holder cavity  36 . That is to say, the cavity axial sealing member  67  forms one of the cavity wall end surface  38 . While the holder cavity  36  is unsealed by the cavity axial sealing member  67  (i.e. while the tool holder  22  is in an unassembled position), the vibration absorbing mass  54  can be inserted into the holder cavity  36 . It is noted that the vibration absorbing mass  54  is reversible. That is to say, the vibration absorbing mass  54  can be inserted into the holder cavity  36  in both longitudinal orientations. 
     In the assembled state of the tool holder  22 , the vibration absorbing mass  54  is disposed within the holder cavity  36 . The holder cavity  36  is sealed by the cavity axial sealing member  67 . Each suspension member  62  is partially located in a respective mass recess  64  and protrudes outwardly therefrom. In accordance with some embodiments of the subject matter of the present application, each suspension member  62  can protrude outwardly from the respective mass recess  64  in a radial direction and/or an axial direction, with respect to the mass central axis E. In this non-limiting example shown in the drawings, the mass recesses  64  intersect the mass edges  61 , and each suspension member  62  can protrude outwardly from the respective mass recess  64  in both the radial direction and the axial direction. Each suspension member  62  can abut the cavity wall surface  38 . Specifically, in the configuration described above where each suspension member  62  can protrude outwardly from the respective mass recess  64  in the radial direction and the axial direction, each suspension member  62  can abut the cavity wall peripheral surface  44  and one of the two cavity wall end surfaces  42  simultaneously. 
     In the assembled position of the tool holder  22 , the vibration absorbing mass  54  can be elongated in the same direction as the tool holder  22 . That is to say, the mass central axis E can be parallel to the holder longitudinal axis B. In particular, the mass central axis E can be co-incident with the holder longitudinal axis B (i.e. the vibration absorbing mass  54  can be co-axial with the tool holder  22 ). 
     In the assembled position of the tool holder  22 , the vibration absorbing mass  54  is connected to the mass housing portion  40  via the at least three suspension members  62 . Thus, the vibration absorbing mass  54  is elastically suspended in the holder cavity  36  by the at least three suspension members  62  contacting the inwardly facing cavity wall surface  38 . It is noted that no part of the mass peripheral surface  58  is in direct contact with the inwardly facing cavity wall surface  38 . In accordance with some embodiments of the subject matter of the present application, the at least three suspension members  62  can be under compressive elastic deformation by contact against the inwardly facing cavity wall surface  38  and a respective mass recess  64 . 
     In the configuration having each suspension member  62  protruding outwardly from the respective mass recess  64  in the axial direction, the suspension member  62  can be under compressive elastic deformation in the axial directions. Additionally, in the configuration having the mass recesses  64  equally angularly offset from one another about the mass central axis E (so that each suspension member  62  has one or more different suspension members  62  that counteract against it) and having each suspension member  62  protruding outwardly from the respective mass recess  64  in the radial direction, the suspension member  62  can also be under compressive elastic deformation in the radial. 
     A portion of the suspension member  62  can be located between the mass peripheral surface  58  and the cavity wall peripheral surface  44 . Likewise, another portion of the suspension member  62  can be located between the mass end surface  56  and the cavity wall end surfaces  44 . Thus, the possibility of the vibration absorbing mass  54  impacting the cavity wall end surface  38 , during metal cutting operations is reduced and even prevented. 
     As an alternative configuration to the foregoing, the cavity wall surface  38  can include a recess (preferably conical), for receiving a portion of a respective suspension member  62 , located away from the periphery of the cavity wall end surface  38 . In this configuration too, the suspension member  62  can be under compressive elastic deformation in both the radial and axial directions simultaneously. The recess prevents the suspension member  62  from sliding along the cavity wall surface  38 . This is particularly advantageous in a configuration having just one suspension member  62  at one of the two mass ends  60 . 
     The anti-vibration arrangement  34  includes an oscillating space  68  formed in the holder cavity  36 . The oscillating space  68  is located between the vibration absorbing mass  54  and the mass housing portion  40  (and more particularly between the vibration absorbing mass  54  and the inwardly facing cavity wall surface  38 ). Stated differently, the mass housing portion  40  and the vibration absorbing mass  54  are spaced apart by the oscillating space  68 . In accordance with some embodiments of the subject matter of the present application, the oscillating space  68  entirely circumferentially surrounds the vibration absorbing mass  54 . That is to say, the oscillating space  68  can extend about the full (360°) angular extent of the cavity central axis D. The oscillating space  68  can form an internal annular slit at the vibration absorbing mass  54 . 
     The vibration absorbing mass  54  is configured to oscillate within the oscillating space  68  upon elastic deformation of the at least three suspension members  62 . Stated differently, the vibration absorbing mass  54  is oscillatingly displaceable within the oscillating space  68  when the at least three suspension members  62  undergo elastic deformation. 
     When the cutting tool  20  encounters a workpiece, it is susceptible to vibration. Typically, for turning or milling cutting operations the vibrations are lateral vibrations. Typically, for drilling cutting operations, the vibrations are torsional vibrations. The vibration absorbing mass  54  oscillates at a vibration frequency. The anti-vibration arrangement is 34 designed to provide the vibration absorbing mass  54  with a vibration frequency close or identical to the natural frequency of the cutting tool  20 , thereby reducing or eliminating vibration of the cutting tool  20 . 
     Advantageously, the anti-vibration arrangement  34  can be tunable (so that the vibration frequency of the vibration absorbing mass  54  matches the natural frequency of the cutting tool  20 ) without the need to disassemble any separable parts. One or more mechanisms, alone or in combination, can be used to alter the vibration frequency at which the vibration absorbing mass  54  oscillates. In one non-limiting example, the at least three suspension member  62  can be pre-loaded. For example, referring to  FIG. 3 , the anti-vibration arrangement  34  can include a tuning member  70  that protrudes into the oscillating space  68 . The tuning member  70  can be formed from the sealing member  67 . The tuning member  70  can abut one or more of the at least three suspension members  62 . The tuning member  70  can be displaceable along the cavity central axis D thereby adjusting the elastic properties of the at least three suspension members  62 . The tuning member  70  can include a planar tuning abutment surface  72 . The tuning abutment surface  72  abuts said suspension members  62  at said one of the mass ends  60 . It is understood that in such a configuration the tuning abutment surface  72  forms part of the inwardly facing cavity wall surface  38 . 
     In accordance with some embodiments of the subject matter of the present application, the oscillating space  68  can be empty. For example, the oscillating space  68  can be devoid of viscous fluid. 
     The vibration absorbing mass  54  can be manufactured from the second metallic material while the mass housing portion  40  can be manufactured from the first metallic material. Moreover, by using various second metallic materials (with varying densities), the weight of the vibration absorbing mass  54  can be altered without changing the dimensions thereof. 
     It should be noted that known anti-vibration arrangements using o-rings for damping require o-rings of different sizes for different diameter masses. On the contrary, one feature of the subject matter of the present application is that the same sized suspension members  62  are suitable for different diameter vibration absorbing masses  54 . It is also noted that o-rings typically require a groove or cut-away portion (for receiving the o-ring) that extends around the entire 360° circumference thereof. For example, U.S. Pat. No. 6,443,673 discloses a conical surface at the end of the absorber mass (i.e. an annular chamfered edge). This cut-away portion is formed by the removal of material and thus detrimentally reduces the weight of the mass. Another feature of the subject matter of the present application is that less material is removed from the vibration absorbing mass  54  for providing the angularly spaced apart mass recesses  64 , as compared to providing for o-rings. 
     It should be further noted that another feature of the subject matter of the present application is that the anti-vibration arrangement  34  is suitable for neutralizing lateral vibrations and torsional vibrations. 
     It should be yet further noted that the configuration having the mass recesses  64  angularly offset about the mass central axis E at each mass end  60  advantageously provides predetermined points of contact on the cavity wall end surface  42  by the suspension members  62 . 
     It should be yet still further noted that the configuration having N greater than or equal to two and less than or equal to eight (with a suspension member located in each mass recess  64 ) provides optimal vibration suppression. 
     Although the subject matter of the present application has been described to a certain degree of particularity, it should be understood that various alterations and modifications could be made without departing from the spirit or scope of the invention as hereinafter claimed.