Tool holder with an anti-vibration arrangement and cutting tool provided with a tool holder

Abstract

An elongated tool holder includes a tool anti-vibration component having a mass housing portion and an anti-vibration arrangement. The anti-vibration arrangement includes a closed interior holder cavity formed in the mass housing portion. The anti-vibration arrangement also includes a vibration absorbing mass that is disposed within the holder cavity and resiliently suspended therein by at least three contact inwardly facing cavity wall surface elastically resilient suspension members of non-toroidal shape. A cutting tool is provided with the tool holder.

Description

Technical Field

[0001] The subject matter of this application generally relates to tool holders, and more specifically to such tool holders having a vibration-resistant arrangement, and even more specifically to such a vibration-resistant arrangement having at least three resilient suspension members. Background Technology

[0002] Tool holders may be equipped with vibration-damping arrangements to suppress vibrations of the tool holder during metal cutting operations. Typically, the vibration-damping arrangement is a spring-mass system comprising a cavity and a vibration-absorbing mass suspended therein by an elastic support member. The cavity may be filled with a viscous fluid.

[0003] In some such vibration-resistant arrangements, the elastic support member can be formed of a ring-type structure (i.e., an O-ring). Examples of such tool-holding systems are disclosed, for example, in US 9,579,730, US 2016 / 305503, US 7,234,379, US 6,443,673, and US 3,774,730.

[0004] In other such vibration-damping arrangements, the elastic support member may be formed of a spherical elastic body. An example of such a tool holding system is described in JP2008100332A, which discloses a vibration-damping tool having a counterweight elastically supported in a hollow portion within a tool body by two generally spherical elastic bodies. The central portion of the tool body and the counterweight is formed into a conical recess, such that the end surfaces of the tool body and the counterweight contacting the spherical elastic bodies readily coincide with the axis of the tool body and the counterweight.

[0005] The purpose of this application is to provide a new and improved vibration-resistant arrangement. Summary of the Invention

[0006] According to a first aspect of the subject matter of this application, a tool holder is provided, which extends along its longitudinal axis and includes:

[0007] The bulk shell portion; and

[0008] Vibration-resistant arrangements, including:

[0009] An internal retainer cavity is formed within the bulk shell portion and has an inwardly facing cavity wall surface;

[0010] A vibration-absorbing mass having a central axis and including two axially opposed mass ends and at least three mass recesses; and

[0011] At least three elastic suspension components shaped as non-toroidal surfaces, each suspension component being partially located in and projecting outward from a corresponding mass recess, wherein:

[0012] The tool holder can be adjusted between an unassembled state and an assembled state, and in the assembled state:

[0013] The vibration-absorbing mass is disposed in the inner retainer cavity and is elastically suspended therein by at least three suspension members that contact the inward-facing cavity wall surface, thereby forming a swing space between the vibration-absorbing mass and the inward-facing cavity wall surface.

[0014] According to a second aspect of the subject matter of this application, a cutting tool is provided, comprising:

[0015] Tool holders of the above types; and

[0016] The cutting part includes at least one cutting insert.

[0017] It is understood that the above is an overview, and the features described below may be applicable to any combination of the subject matter of this application. For example, any of the following features may be applicable to a tool holder or a cutting tool:

[0018] At least three suspension components can be subjected to compressive elastic deformation by abutting against the cavity wall surface facing inward and the corresponding mass recess.

[0019] At least three suspension components can be formed of a material different from the material of the vibration-absorbing mass.

[0020] In the unassembled state, the vibration-absorbing mass can be positioned outside the internal retainer cavity. Each of at least three suspension members can be releasably held in one of the corresponding three mass recesses of the vibration-absorbing mass by a corresponding suspension member under compressive elastic deformation, wherein the suspension member is under compressive elastic deformation by abutting only against the surface surrounding the mass recess of the corresponding one of the at least three mass recesses.

[0021] Each of the at least three suspension components may have a spherical shape defined by the radius of the suspension component.

[0022] Vibration-absorbing masses can elongate along their central axis.

[0023] In the assembled state of the tool holder, the central axis of the mass can be parallel to the longitudinal axis of the holder.

[0024] The central axis of the mass can coincide with the longitudinal axis of the retainer.

[0025] Vibration-absorbing masses can have a constant cross-sectional area in a plane oriented perpendicular to the central axis of the mass.

[0026] In the end view of the vibration-absorbing mass, each mass recess can be subtend from the central axis of the mass at a recess angle. For any given mass end with two or more mass recesses, the mass recesses can be equiangularly spaced from each other about the central axis of the mass at a recess separation angle. The recess separation angle can be smaller than the mass recess angle.

[0027] At least three block recesses may be formed at two opposite block ends, with at least one block recess formed at each block end.

[0028] The vibration-absorbing mass may include two end surfaces and a peripheral surface extending therebetween about a central axis of the mass, the two end surfaces and the peripheral surface intersecting to form two edges of the mass. Each of at least three recesses may be at least partially formed in one of the two end surfaces of the mass.

[0029] Each of the at least three block recesses may be partially formed in one of the two block end surfaces and partially formed in the block peripheral surface so as to intersect one of the two block edges.

[0030] Each end surface of a mass can be rotated symmetrical about the central axis of the mass.

[0031] The end surfaces of the two masses can be the same.

[0032] The end surfaces of the two masses can rotate relative to each other by a rotation angle about the central axis of the masses.

[0033] For any end of a mass having two or more concave portions, the concave portions can be offset angularly about the central axis of the mass by an offset angle. The rotation angle can be equal to half the offset angle.

[0034] Each suspension component can protrude outward from the corresponding block recess in both the radial and axial directions relative to the block's central axis.

[0035] The peripheral surface of the mass on the far side of the end surface can have a cylindrical shape defined by the mass radius.

[0036] At least three suspension components can have a spherical shape defined by the radius of the suspension component. The mass radius can be between three and four times the size of the suspension component radius.

[0037] The end surfaces of the two masses can be planar and oriented transversely to the central axis of the masses.

[0038] For any end of a mass having two or more recesses, the recesses may be offset from each other at an angle about the central axis of the mass.

[0039] The concave parts of a mass can be offset from each other at equal angles around the central axis of the mass by an offset angle.

[0040] The cavity wall surface may include two opposing cavity wall end surfaces and a cavity wall peripheral surface extending therebetween, the cavity wall peripheral surface extending about the central axis of the cavity. In the assembled position of the tool holder, each suspension component may simultaneously abut the cavity wall peripheral surface and one of the two planar cavity wall end surfaces.

[0041] The end surfaces of the two cavity walls can be flat.

[0042] The vibration-absorbing mass can include an equal number of N mass recesses at the ends of each mass.

[0043] N can be equal to 6.

[0044] At least three mass recesses may be formed at two opposing mass ends (60). The vibration-damping arrangement may include a tuning member that is displaceable along the central axis of the cavity and may abut a suspension member at one of the mass ends.

[0045] The tuning member may include a planar tuning abutment surface. The tuning abutment surface may abut the suspension member at one of the ends of the mass.

[0046] The oscillating space can be free of viscous fluid.

[0047] The mass shell portion may include a first metallic material. The vibration-absorbing mass may include a second metallic material. The second metallic material may be denser than the first metallic material.

[0048] The cutting portion can be releasably attached to the tool holder.

[0049] Vibration-resistant structures can be installed at the front end of the cutting tool.

[0050] Cutting tools can be rotary cutting tools designed to rotate about an axis of rotation. Attached Figure Description

[0051] To better understand this application and to illustrate how it can be implemented in practice, reference will now be made to the accompanying drawings, in which:

[0052] Figure 1 This is a perspective view of the cutting tool according to this application, showing the vibration-resistant arrangement;

[0053] Figure 2 It is based on this application Figure 1 Exploded perspective view of the tool holder in the middle;

[0054] Figure 3 yes Figure 2Axial cross-sectional view of the tool holder in the image;

[0055] Figure 4 yes Figure 2 Tool holder along Figure 3 A radial cross-sectional view taken by line IV-IV in the middle;

[0056] Figure 5 yes Figure 2 Perspective view of the vibration-resistant arrangement in the middle;

[0057] Figure 6 yes Figure 1 An exploded perspective view of the vibration-resistant arrangement of the components;

[0058] Figure 7 yes Figure 5 Side view of the vibration-resistant arrangement of the parts;

[0059] Figure 8 yes Figure 5 End views of the vibration-resistant arrangement of the parts; and

[0060] Figure 9 yes Figure 5 The vibration-resistant arrangement of the parts along Figure 7 The radial cross-sectional view is taken from line IX-IX in the diagram.

[0061] It will be understood that, for the sake of simplicity and clarity, the elements shown in the figures are not necessarily drawn to scale. For example, for clarity, the dimensions of some elements may be exaggerated relative to others, or several physical components may be included in a single functional block or element. Furthermore, where deemed appropriate, reference numerals may be repeated between figures to indicate corresponding or similar elements. Detailed Implementation

[0062] In the following description, various aspects of the subject matter of this application will be described. For purposes of explanation, specific configurations and details have been elaborated sufficiently to provide a thorough understanding of the subject matter of this application. However, it will also be apparent to those skilled in the art that the subject matter of this application can be practiced without the specific configurations and details presented herein.

[0063] First, pay attention Figure 1The figure illustrates a cutting tool 20 for chip removal, thus depicting an aspect of this application. The cutting tool 20 has a longitudinal axis A. According to some embodiments of the subject matter of this application, the cutting tool 20 can be a rotary cutting tool. In other words, the cutting tool 20 is designed to rotate about a rotational axis. In this non-limiting example shown in the figure, the cutting tool 20 is a milling tool. However, the subject matter of this application is not limited to milling tools and can also be applied (e.g., but not limited to) drilling tools. The subject matter of this application can also be applied to non-rotational cutting tools, such as boring bars. For such non-rotational cutting tools, the cutting tool 20 is not designed to rotate about the longitudinal axis A in the direction of rotation.

[0064] The cutting tool 20 includes a tool holder 22. The cutting tool 20 also includes a cutting portion 24, which 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. According to some embodiments of the subject matter of this application, at least one cutting insert 26 may be releasably attached to the cutting portion 24. The cutting portion 24 may be integrally formed with the tool holder 22. Alternatively, the cutting portion 24 may be releasably attached to the tool holder 22. The cutting portion 24 may be located at the front end of the tool holder 22.

[0065] Now for reference Figure 2 The image shows a tool holder 22, thus depicting another aspect of this application. The tool holder 22 has a retainer longitudinal axis B, which defines an opposing forward direction D. F Rear direction D R The tool holder 22 extends along the longitudinal axis B of the holder. According to some embodiments of the subject matter of this application, the cutting tool 20 and the tool holder 22 can be coaxial with each other. It should be noted that the two elements are coaxial when their longitudinal axes coincide (align with each other), such as the cutting tool 20 and the tool holder 22 in the present case.

[0066] It should also be noted that throughout the specification and claims, the terms "forward" and "backward" refer to the following respectively: Figure 3 The relative positions of the holder along its longitudinal axis B in the left and right directions. Generally, the forward direction is the direction toward the cutting portion 24.

[0067] According to some embodiments of the subject matter of this application, the tool holder 22 may include two opposing holder end surfaces 30 and a holder peripheral surface 32 extending therebetween. The holder peripheral surface 32 may extend about the holder longitudinal axis B.

[0068] The tool holder 22 includes a bulk housing portion 40 and a vibration-damping arrangement 34. The tool vibration-damping arrangement 34 is designed to reduce or eliminate vibration of the cutting tool 20 when it performs metal cutting operations. According to some embodiments of the subject matter of this application, the vibration-damping arrangement 34 may be located at the front end of the cutting tool 20.

[0069] The vibration-resistant arrangement 34 includes an internal retainer cavity 36 formed within the mass housing portion 40. In other words, the internal retainer cavity 36 is enclosed within the mass housing portion 40. The retainer cavity 36 is formed by an inwardly facing cavity wall surface 38. The cavity wall surface 38 defines the retainer cavity 36 from the mass housing portion 40. The mass housing portion 40 surrounds the retainer cavity 36. The retainer cavity 36 has a cavity central axis D. According to some embodiments of the subject matter of this application, the retainer cavity 36 may extend along the cavity central axis D. The retainer cavity 36 may extend in the same direction as the tool retainer 22. Specifically, the retainer cavity 36 may be coaxial with the tool retainer 22. The cavity wall surface 38 may include two opposing cavity wall end surfaces 42 and a cavity wall peripheral surface 44 extending therebetween. The cavity wall peripheral surface 44 may extend about the cavity central axis D.

[0070] For further reference Figure 3 The diagram shows an axial cross-sectional view (taken in a plane including the central axis D of the cavity) of a retainer cavity 36 passing through the peripheral surface 44 of the cavity wall, the retainer cavity 36 having a transverse cross-section. According to some embodiments of the subject matter of this application, the transverse cross-section of the cavity may be uniform along the central axis D. The peripheral surface 44 of the cavity wall may have a generally cylindrical shape. The peripheral surface 44 of the cavity wall may have a cylindrical shape near the two end surfaces 42 of the cavity wall (where, as described later in the specification, the peripheral surface 44 of the cavity wall abuts the suspension member 62). The two end surfaces 42 of the cavity wall may be planar and oriented transversely to the central axis D of the cavity. The two end surfaces 42 of the cavity wall may be oriented perpendicularly to the central axis D of the cavity.

[0071] Return to reference Figure 1 as well as Figure 2 The vibration-damping arrangement 34 also includes a vibration-absorbing mass 54. According to some embodiments of the subject matter of this application, the vibration-absorbing mass 54 may be rigid. In some embodiments, when the mass housing portion 40 is formed of a first metallic material (such as steel), the vibration-absorbing mass 54 may be formed of a denser second metallic material (such as tungsten).

[0072] refer to Figure 4-7The vibration-absorbing mass 54 has a central axis E. The vibration-absorbing mass 54 includes two axially opposed mass ends 60. The two axially opposed mass ends 60 are spaced apart from each other along the central axis E. According to some embodiments of the subject matter of this application, the vibration-absorbing mass 54 may include two opposing mass end surfaces 56 and a mass peripheral surface 58 extending therebetween. The mass peripheral surface 58 may 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 may intersect to form two mass edges 61. The vibration-absorbing mass 54 may extend along the mass central axis E. The vibration-absorbing mass 54 may have a substantially constant cross-sectional area in a plane oriented perpendicular to the mass central axis E.

[0073] refer to Figure 2 as well as Figure 5-7 The vibration-absorbing mass 54 includes at least three mass recesses 64. Each mass recess 64 is recessed within the vibration-absorbing mass 54. As described later in the specification, the at least three mass recesses 64 are designed to receive suspension components. Each mass recess 64 is defined by a peripheral surface 66. According to some embodiments of the subject matter of this application, the at least three mass recesses 64 may be identical. The at least three mass recesses 64 may be recessed. The at least three mass recesses 64 may have a partially spherical basic shape. In other words, the peripheral surface 66 of each mass recess may be generally located on an imaginary sphere, facing inward toward the center of said imaginary sphere.

[0074] As in Figure 6 As best seen in some embodiments of the subject matter of this application, at least three mass recesses 64 may be formed at two opposing mass ends 60, and wherein at least one mass recess 64 is formed at each mass end 60. Each of the at least three mass recesses 64 may be at least partially formed in the surfaces 56 of the two mass ends. Specifically, each of the at least three mass recesses 64 may be disposed at the periphery of the vibration-absorbing mass 54. Each of the at least three mass recesses 64 may be partially formed in one of the surfaces 56 of the two mass ends and partially formed in the peripheral surface 58 of the mass so as to intersect with one of the edges 61 of the two mass. None of the at least three mass recesses 64 intersects the central axis E of the mass. It should be noted that the at least three mass recesses 64 are not annular recesses extending over the entire 360° circumference of the central axis D of the cavity. Therefore, they are not suitable for receiving O-rings.

[0075] refer to Figure 8For any mass end 60 having two or more mass recesses 64, the mass recesses 64 can be offset from each other at an angle about the mass central axis E. The mass recesses 64 can be offset from each other at an angle γ about the mass central axis E. This configuration provides a stable, elastic suspension for the vibration-absorbing mass 54 within the internal retainer cavity 36. In the 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 spaced apart from each other at an angle θ about the mass central axis E.

[0076] According to some embodiments of the subject matter of this application, the vibration-absorbing mass block 54 may include an equal number of N (N is greater than one) mass block recesses 64 at each mass block end 60, thereby forming a total of 2*N mass block recesses 64 in the vibration-absorbing mass block 54. In the non-limiting example shown in the figure, N may be equal to six (in other words, there are a total of twelve mass block recesses 64, six at each end of the mass block end 60).

[0077] refer to Figure 7 According to some embodiments of the subject matter of this application, the end surface 56 of the mass may be planar and oriented perpendicular to the central axis E of the mass. (See reference...) Figure 8 The peripheral surface 58 of the mass on the distal side of the mass end surface 56 may have a cylindrical shape defined by the mass radius R2. Each mass end surface 56 (including any mass recess 64 located thereon) may be rotationally symmetrical about the mass central axis E. Two mass end surfaces 56 may be identical. Two mass end surfaces 56 may be rotated and offset from each other about the mass central axis E by a rotation angle α. The rotation angle α may be equal to half of the offset angle γ. In other words, in a view along the mass central axis E, for any given pair of adjacent mass recesses 64 at a given mass end surface 56, the mass recesses 64 at the opposite mass end surface 56 are angularly located exactly at the midpoint between the given pair of adjacent mass recesses 64. (See reference) Figure 8 In the end view of the vibration-absorbing mass 54, each mass recess 64 is oriented from the central axis E of the mass towards a mass recess angle β. The mass recess angle β is defined by the angular end of the mass recess 64 about the central axis E of the mass. The recess separation angle θ can be smaller than the mass recess angle β.

[0078] According to some embodiments of the subject matter of this application, the peripheral surface 44 of the cavity wall may have a shape that matches the shape of the peripheral surface 58 of the mass. One or both of the two end surfaces 42 of the cavity wall may have a shape that matches the shape of the corresponding end surface 56 of the mass. Therefore, the retainer cavity 36 may have a shape that matches the shape of the vibration-absorbing mass 54.

[0079] The vibration-damping arrangement 34 includes at least three resilient suspension members 62. Each suspension member 62 is defined by a peripheral surface 63. All three suspension members 62 are elastically deformable. According to some embodiments of the subject matter of this application, the number of suspension members 62 may match the number of mass recesses 64. The at least three suspension members 62 may be formed of a material different from the material of the vibration-absorbing mass 54. In some embodiments, the suspension members 62 are made of rubber having a Durometer hardness between 60A and 95A.

[0080] At least three suspension components 62 are non-toroidal (i.e., non-ring-shaped). In other words, at least three suspension components 62 are not O-rings. According to some embodiments of the subject matter of this application, generally, at least three suspension components 62 may have shapes corresponding to the shapes of at least three mass recesses 64. At least three suspension components 62 may be spheres. At least three suspension components 62 may have a spherical shape (i.e., a ball). In other words, each suspension peripheral surface component 63 may be located on an imaginary sphere, facing outwards from the center of the imaginary sphere. Reference Figure 8 as well as Figure 9 Each suspension component 62 can be defined by a suspension component radius R1. The mass radius R2 can be between three and four times the size of the suspension component radius R1. In other words, the mass radius R2 can be between 300% and 400% of the size of the suspension component radius R1. Preferably, the mass radius R2 can be between 325% and 375% of the size of the suspension component radius R1. At least three suspension components 62 can be solid. In other words, at least three suspension components 62 are not hollow. At least three suspension components 62 are not fluid.

[0081] 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 inner holder cavity 36. According to some embodiments of the subject matter of this application, each of the at least three suspension members 62, which is under compressive elastic deformation by contacting only the peripheral surface 66 of the corresponding one of the mass recesses 64, can be releasably held in the corresponding one of the at least three mass recesses 64 of the vibration-absorbing mass 54. For example, each suspension member 62 can be pressed into the corresponding mass recess 64 such that the peripheral surface 63 of the suspension member is pressed against and abuts the peripheral surface 66 of the mass recess.

[0082] According to some embodiments of the subject matter of this application, the tool holder 22 includes a forward direction D FAn axial sealing member 67 defines and seals the retainer cavity 36. In other words, the axial sealing member 67 forms one of the cavity wall end surfaces 38. When the retainer cavity 36 is not sealed by the axial sealing member 67 (i.e., when the tool retainer 22 is in the unassembled position), the vibration-absorbing mass 54 can be inserted into the retainer cavity 36. It should be noted that the vibration-absorbing mass 54 is reversible. In other words, the vibration-absorbing mass 54 can be inserted into the retainer cavity 36 in two longitudinal orientations.

[0083] 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 a cavity axial sealing member 67. Each suspension member 62 is partially located in and protrudes outward from a corresponding mass recess 64. According to some embodiments of the subject matter of this application, each suspension member 62 may protrude outward from the corresponding mass recess 64 in a radial and / or axial direction relative to the mass central axis E. In this non-limiting example shown in the figures, the mass recess 64 intersects with the mass edge 61, and each suspension member 62 may protrude outward from the corresponding mass recess 64 in both the radial and axial directions. Each suspension member 62 may abut a cavity wall surface 38. Specifically, in the above configuration, where each suspension member 62 may protrude outward from the corresponding mass recess 64 in both the radial and axial directions, each suspension member 62 may simultaneously abut abut a cavity wall peripheral surface 44 and one of the two cavity wall end surfaces 42.

[0084] In the assembled position of the tool holder 22, the vibration-absorbing mass 54 can extend in the same direction as the tool holder 22. In other words, the central axis E of the mass can be parallel to the longitudinal axis B of the holder. Specifically, the central axis E of the mass can coincide with the longitudinal axis B of the holder (i.e., the vibration-absorbing mass 54 can be coaxial with the tool holder 22).

[0085] In the assembled position of the tool holder 22, the vibration-absorbing mass 54 is connected to the mass housing portion 40 via at least three suspension members 62. Thus, the vibration-absorbing mass 54 is elastically suspended within the holder cavity 36 by the at least three suspension members 62 contacting the inward-facing cavity wall surface 38. It should be noted that no portion of the mass peripheral surface 58 is in direct contact with the inward-facing cavity wall surface 38. According to some embodiments of the subject matter of this application, the at least three suspension members 62 can be subjected to compressive elastic deformation by abutting against the inward-facing cavity wall surface 38 and the corresponding mass recess 64.

[0086] In a configuration where each suspension member 62 protrudes outward from its corresponding mass recess 64 in the axial direction, the suspension member 62 can be subjected to compressive elastic deformation in the axial direction. Alternatively, in a configuration where the mass recesses 64 are offset from each other at equal angles about the mass central axis E (such that each suspension member 62 has one or more different suspension members 62 opposing it) and each suspension member 62 protrudes outward from its corresponding mass recess 64 in the radial direction, the suspension member 62 can also be subjected to compressive elastic deformation in the radial direction.

[0087] A portion of the suspension component 62 may be located between the peripheral surface 58 of the mass and the peripheral surface 44 of the cavity wall. Similarly, another portion of the suspension component 62 may be located between the end surface 56 of the mass and the end surface 44 of the cavity wall. Therefore, during metal cutting operations, the possibility of the vibration-absorbing mass 54 impacting the end surface 38 of the cavity wall is reduced or even prevented.

[0088] As an alternative configuration described above, the cavity wall surface 38 may include a recess (preferably conical) for receiving a portion of the respective suspension member 62, the recess being positioned away from the periphery of the cavity wall end surface 38. In this configuration, the suspension member 62 can also be subjected to 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 where only one suspension member 62 is located at one of the two mass ends 60.

[0089] The vibration-damping arrangement 34 includes a swing space 68 formed in the retainer cavity 36. The swing space 68 is located between the vibration-absorbing mass 54 and the mass housing portion 40 (and more specifically between the vibration-absorbing mass 54 and the inwardly facing cavity wall surface 38). In other words, the mass housing portion 40 and the vibration-absorbing mass 54 are spaced apart by the swing space 68. According to some embodiments of the subject matter of this application, the swing space 68 is completely circumferentially surrounding the vibration-absorbing mass 54. In other words, the swing space 68 can extend over a full (360°) angular range about the central axis D of the cavity. The swing space 68 can form an internal annular slit at the vibration-absorbing mass 54.

[0090] The vibration-absorbing mass 54 is configured to oscillate within the oscillation space 68 during the elastic deformation of at least three suspension members 62. In other words, the vibration-absorbing mass 54 is oscillating and displaceable within the oscillation space 68 when at least three suspension members 62 undergo elastic deformation.

[0091] When the cutting tool 20 encounters the workpiece, it is susceptible to vibration. Typically, for turning or milling operations, the vibration is lateral. Typically, for drilling operations, the vibration is torsional. The vibration-absorbing mass 54 oscillates at the vibration frequency. The anti-vibration arrangement 34 is designed such that the vibration-absorbing mass 54 provides a vibration frequency close to or the same as the natural frequency of the cutting tool 20, thereby reducing or eliminating the vibration of the cutting tool 20.

[0092] Advantageously, the vibration-damping arrangement 34 can be tunable (such that the vibration frequency of the vibration-absorbing mass 54 matches the natural frequency of the cutting tool 20) without disassembling any separable parts. One or more mechanisms, individually or in combination, can be used to change the vibration frequency of the vibration-absorbing mass 54 as it oscillates. In a non-limiting example, at least three suspension members 62 can be preloaded. For example, refer to... Figure 3 The vibration-damping arrangement 34 may include a tuning member 70 projecting into the swing space 68. The tuning member 70 may be formed by a sealing member 67. The tuning member 70 may abut one or more of at least three suspension members 62. The tuning member 70 may 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 may include a planar tuning abutment surface 72. The tuning abutment surface 72 abuts the suspension member 62 at one of the mass ends 60. It should be understood that in such a configuration, the tuning abutment surface 72 forms part of the inwardly facing cavity wall surface 38.

[0093] According to some embodiments of the subject matter of this application, the oscillation space 68 may be empty. For example, the oscillation space 68 may be free of viscous fluid.

[0094] The vibration-absorbing mass 54 can be made of a second metallic material, while the mass shell portion 40 can be made of a first metallic material. Furthermore, by using various second metallic materials (with different densities), the weight of the vibration-absorbing mass 54 can be changed without altering its dimensions.

[0095] It should be noted that known vibration-damping arrangements using O-rings for damping require O-rings of different sizes for masses of different diameters. In contrast, a feature of the subject matter of this application is that the same size suspension member 62 is suitable for vibration-absorbing masses 54 of different diameters. It should also be noted that O-rings typically require a groove or cutout extending around their entire 360° circumference (for receiving the O-ring). For example, US 6,443,673 discloses a conical surface at the end (i.e., the annular chamfered edge) of the absorbing mass. This cutout is formed by material removal and thus disadvantageously reduces the weight of the mass. Another feature of the subject matter of this application is that less material is removed from the vibration-absorbing mass 54 for the angledly spaced mass recesses 64 compared to the case where O-rings are used.

[0096] It should also be noted that another feature of the subject matter of this application is that the vibration-resistant arrangement 34 is suitable for neutralizing both lateral and torsional vibrations.

[0097] It should also be noted that the configuration of a mass recess 64 at each mass end 60, which is angularly offset about the mass central axis E, advantageously provides a predetermined contact point on the cavity wall end surface 42 that is contacted by the suspension member 62.

[0098] It should also be noted that a configuration where N is greater than or equal to two and less than or equal to eight (and the suspension components are located in each mass recess 64) provides optimal vibration suppression.

[0099] Although the subject matter of this application has been described in a certain degree of specificity, it should be understood that various changes and modifications may be made without departing from the spirit or scope of the invention as claimed below.

Claims

1. A tool holder (22) elongated along a holder longitudinal axis (B) thereof and comprising: a mass housing portion (40); and a vibration damping arrangement (34) comprising: an inner holder cavity (36) formed in the mass housing portion (40) and having an inwardly facing cavity wall surface (38); a vibration absorbing mass (54) having a mass central axis (E) and comprising two axially opposite mass end portions (60) each having a mass end portion surface (56); a mass peripheral surface (58) extending around the mass central axis (E) between the two mass end portion surfaces (56), the two mass end portion surfaces (56) and the mass peripheral surface (58) intersecting to form two mass edges (61); at least three mass recesses (64) formed at each mass end portion (60), each mass recess (64) having a resilient suspension member (62) of non-annular shape, the suspension member (62) being partially located in the mass recess (64) and protruding outwardly therefrom, wherein: all of the at least three mass recesses (64) at each mass end portion (60) have a non-annular shape and are not configured for receiving an o-ring; all of the at least three mass recesses (64) at each mass end portion (60) are radially spaced apart from the mass central axis (E); at each mass end portion (60), each of the at least three mass recesses (64) is partially formed in a corresponding one of the two mass end portion surfaces (56) and partially formed in the mass peripheral surface (58) so as to intersect one of the two mass edges (61); in an end view of the vibration absorbing mass (54): all of the at least three suspension members (62) at each of the two mass end portions (60) are visible; and all of the at least three suspension members (62) at one mass end portion (60) are considered angularly offset with respect to all of the at least three suspension members (62) provided at the opposite mass end portion (60); and the tool holder (22) is adjustable between an unassembled state and an assembled state, and in the assembled state: the vibration absorbing mass (54) is provided in the inner holder cavity (36) and is resiliently suspended therein by the at least three suspension members (62) at each mass end portion contacting the inwardly facing cavity wall surface (38), and thereby forming a pendulum space (68) between the vibration absorbing mass (54) and the inwardly facing cavity wall surface (38). the at least three suspension members (62) are under compressive elastic deformation by abutting contact against the inwardly facing cavity wall surface (38) and the respective mass recess (64).

2. The tool holder (22) according to claim 1, wherein, the at least three suspension members (62) are formed of a material different from that of the vibration absorbing mass (54).

3. The tool holder (22) according to claim 1, wherein, in the unassembled state:

4. The tool holder (22) according to claim 3, wherein, the vibration absorbing mass (54) is provided outside the inner holder cavity (36); ​ and each of the at least three suspension members (62) is releasably held in a respective one of at least three mass pockets (64) of the vibration absorbing mass (54), wherein the respective suspension member (62) is in compressive elastic deformation by abutting only against a mass pocket peripheral surface (66) contacting the respective one of the at least three mass pockets (64).

5. The tool holder (22) according to claim 1, wherein, each of the at least three suspension members (62) has a spherical shape defined by a suspension member radius (R1).

6. The tool holder (22) of claim 1, wherein: in an end view of the vibration absorbing mass (54): each mass pocket (64) subtends a mass pocket angle (β) from a mass center axis (E); for any given mass end (60) having two or more mass pockets (64), the mass pockets (64) are equiangularly spaced from one another about the mass center axis (E) by a pocket separation angle (θ); and the pocket separation angle (θ) is less than the mass pocket angle (β).

7. The tool holder (22) according to claim 1, wherein, each mass end surface (56) is rotationally symmetric about the mass center axis (E).

8. The tool holder (22) according to claim 1, wherein, the two mass end surfaces (56) are rotationally offset from one another about mass center axis (E) by a rotational angle (α).

9. The tool holder (22) according to claim 1, wherein, each suspension member (62) projects outwardly from the respective mass pocket (64) in both a radial direction and an axial direction relative to the mass center axis (E).

10. The tool holder (22) according to claim 1, wherein, the mass peripheral surface (58) distal to the mass end surfaces (56) has a cylindrical shape defined by a mass radius (R2).

11. The tool holder (22) of claim 10, wherein: the at least three suspension members (62) have a spherical shape defined by a suspension member radius (R1); and the mass radius (R2) is between three to four times the size of the suspension member radius (R1).

12. The tool holder (22) according to claim 1, wherein, the mass pockets (64) are equiangularly offset from one another about the mass center axis (E) by an offset angle (γ).

13. The tool holder (22) of claim 1, wherein: the cavity wall surface (38) includes two opposing cavity wall end surfaces (42) and a cavity wall peripheral surface (44) extending therebetween, the cavity wall peripheral surface (44) extending about a cavity center axis (D); and in the assembled position of the tool holder (22), each suspension member (62) simultaneously abuts the cavity wall peripheral surface (44) and one of the two planar cavity wall end surfaces (42).

14. The tool holder (22) according to claim 1, wherein, the vibration absorbing mass (54) includes an equal number of N mass pockets (64) at each mass end (60).

15. The tool holder (22) according to claim 14, wherein, N＝6。 16. The tool holder (22) according to claim 1, wherein, the pendulum space (68) is free of viscous fluid.

17. The tool holder (22) of claim 1, wherein: the mass housing portion (40) comprises a first metallic material; the vibration absorbing mass (54) comprises a second metallic material; and the second metallic material is denser than the first metallic material.

18. A cutting tool (20) comprising: The tool holder (22) according to claim 1; as well as The cutting portion (24) includes at least one cutting blade (26).

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