Tool holder with vibration isolation device and coolant passage, and cutting tool equipped with the tool holder

Abstract

The elongated tool holder (22) includes a mass housing portion (40) having a housing outer periphery surface, an outer sleeve having a sleeve bore wall surface, and a vibration isolator (34). An elongated groove (92) is formed in one of the housing outer periphery surface and the sleeve bore wall surface. In an assembled condition of the tool holder, the groove located at the common interface of the housing outer periphery surface and the sleeve bore wall surface forms a groove coolant passage. The groove coolant passage forms a portion of an overall tool holder coolant passage spaced from the vibration isolator, thus isolating the coolant from the vibration isolator. A cutting tool (20) incorporates the tool holder.

Description

[Technical field]

[0001] The subject matter of this application relates generally to tool holders, particularly to such tool holders having vibration isolation devices, and more particularly to such tool holders having coolant passages. [Background technology]

[0002] The tool holder may include a vibration isolator that suppresses vibration of the tool holder during metal cutting operations. Typically, the vibration isolator is a spring-mass system that includes a cavity and a vibration-absorbing mass suspended within the cavity by an elastic support member. The cavity may be filled with a viscous fluid.

[0003] In some such vibration isolation devices, further coolant passages are provided which supply cooling fluid to the cutting area. An example of such a tool holding system is disclosed, for example, in US 7,681,869 B2. In its FIG. 2, US 7,681,869 B2 discloses a vibration damper 1 through which an axial bore 6 passes. Inside the boring bar there is an axially extending longitudinal tube 3 which is generally adapted to be rigidly fixed at its outer end or inside the boring bar to the object to be damped. The tube 3 is adapted to guide a cooling fluid through itself which communicates with a passage extending further into the boring bar. Summary of the Invention [Problem to be solved by the invention]

[0004] It is an object of the present subject matter to provide a new and improved tool holder having vibration isolation and coolant passages. [Means for solving the problem]

[0005] According to a first aspect of the present subject matter, there is provided a tool holder elongated along a holder longitudinal axis defining opposite forward and rearward directions, the tool holder configured to have a cutting portion secured to a front end of the tool holder, the tool holder comprising: An outer sleeve comprising: opposing forward and rearward sleeve end faces and an outer circumferential sleeve surface extending between the forward and rearward sleeve end faces; and a sleeve hole having a sleeve hole wall surface opening to a front sleeve end surface and a rear sleeve end surface; an outer sleeve comprising: A mass housing portion, opposing front and rear housing end faces and a housing perimeter extending between the front and rear housing end faces; and An inner holder cavity having an inward facing cavity wall a mass housing portion comprising: 1. A vibration isolation device, comprising: a vibration absorbing mass having two opposing mass end faces and a mass perimeter extending between the mass end faces; Two elastic suspension members A vibration isolation device comprising: Equipped with The elongated groove is formed in one of the housing outer circumferential surface and the sleeve hole wall surface; The tool holder is adjustable between an unassembled state and an assembled state, and in the assembled state a vibration absorbing mass disposed within the inner holder cavity and resiliently suspended within the inner holder cavity by two suspension members contacting the inwardly facing cavity wall surfaces; the mass housing portion is at least partially positioned within the sleeve bore such that at least a portion of the sleeve bore wall surface surrounds at least a portion of the housing outer periphery about the holder longitudinal axis, thereby defining a common boundary surface; the grooves are located at the common interface, thereby forming groove coolant passages; The groove coolant passage is part of a toolholder coolant passage having an external coolant inlet and an external coolant outlet in fluid communication with each other.

[0006] According to a second aspect of the present subject matter, there is provided a cutting tool comprising: A tool holder of the kind described above, A cutting part located at the front end of the tool holder; and the cutting portion comprises at least one cutting insert.

[0007] The above is a summary, and the features described below may be applicable to the subject matter of the present application in any combination. For example, it should be understood that any of the following features may be applicable to a tool holder or a cutting tool: The groove may be formed in the outer periphery of the housing. The sleeve bore wall may open to the rear sleeve end face. The groove may extend linearly along a groove axis, which may be parallel to the holder longitudinal axis in the assembled state of the tool holder. The mass housing portion may comprise a front housing portion and a rear housing portion, the front housing portion being forward of the rear housing portion and having a larger radial dimension than the rear housing portion, and in an assembled state of the tool holder, only the rear housing portion may be located within the sleeve bore. The housing outer circumferential surface may comprise a front housing outer circumferential surface on the front housing portion, a rear housing outer circumferential surface on the rear housing portion, and a housing step surface connecting the front housing outer circumferential surface and the rear housing outer circumferential surface. The front housing portion may comprise a front housing coolant passageway at a rear end thereof opening into the housing step surface. In an assembled state of the tool holder, the groove coolant passageway may extend into the front housing coolant passageway. The front housing coolant passageway may be part of the tool holder coolant passageway. The front housing coolant passageway may further open to the outer housing surface at a forward end of the front housing portion to form a coolant outlet. The mass housing portion may comprise a housing recess, the housing recess having an inwardly facing recess wall surface opening into the rear housing end face. The tool holder may comprise a cavity axial sealing member. In an assembled state of the tool holder, the cavity axial sealing member may be located within the housing recess and delimit the holder cavity in a rearward direction, such that a front portion of the housing recess forms an internal holder cavity. The rear housing portion may comprise a rear housing coolant passageway opening into the recess wall surface and the rear housing outer peripheral surface. In an assembled state of the tool holder, the rear housing coolant passageway may be rearward of the cavity axial sealing member, and the rear housing coolant passageway may be part of the tool holder coolant passageway. The outer sleeve may include a forward outer sleeve component and a rearward outer sleeve component, the forward outer sleeve component being forward of the rearward outer sleeve component, the forward outer sleeve component and the rearward outer sleeve component being fixedly engageable with one another. In the assembled state of the tool holder, the front sleeve end face and the housing step face may abut against one another. The rear housing outer circumferential surface may comprise a front rear housing outer circumferential surface and a rear rear housing outer circumferential surface spaced apart in the axial direction, and an intermediate rear housing outer circumferential surface extending between the front rear housing outer circumferential surface and the rear rear housing outer circumferential surface, the front rear housing outer circumferential surface being closer to the front housing portion than the rear rear housing outer circumferential surface. In an assembled state of the tool holder, at least the front rear housing outer circumferential surface and the rear rear housing outer circumferential surface may abut against the sleeve hole wall surface, respectively. The groove may be formed in the housing outer circumferential surface. The groove may have two groove ends. The front rear housing outer circumferential surface may intersect with the housing step surface. One of the two groove ends may be disposed on the rear rear housing outer circumferential surface. The other of the two groove ends may be disposed at a line of intersection between the front rear housing outer circumferential surface and the housing step surface. The intermediate rear housing outer circumferential surface may be radially recessed relative to the front rear housing outer circumferential surface and the rear rear housing outer circumferential surface. In an assembled state of the tool holder, the intermediate rear housing outer circumferential surface may be spaced apart from the sleeve hole wall surface. The mass housing portion may include a housing recess with an inwardly facing recess wall opening to the rear housing end face. The tool holder may include a cavity axial sealing member. In an assembled state of the tool holder, the cavity axial sealing member may be located within the housing recess and delimit the holder cavity in a rearward direction such that a front portion of the housing recess forms an internal holder cavity. In an assembled condition of the toolholder, the recess wall may open into the rear housing end face to form the coolant inlet. A portion of the housing recess extending from the coolant inlet may be part of the toolholder coolant passageway. The outer sleeve may comprise a sleeve material. The mass housing portion may comprise a housing body material. The sleeve material may be denser than the housing body material. The sleeve material may be a carbide. The cutting portion may be releasably attachable to the tool holder. The coolant outlet may be rotationally aligned with the cutting insert about the holder longitudinal axis.

[0008] For a better understanding of the present application and to show how it may be carried into practice, reference is now made to the accompanying drawings, in which: [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of a cutting tool according to the present application showing an anti-vibration device. [Diagram 2] FIG. 2 is an exploded perspective view of the cutting tool of FIG. 1 according to the present application. [Diagram 3] FIG. 2 is an axial cross-sectional view of the cutting tool of FIG. [Figure 4] 4 is a radial cross-sectional view of the cutting tool of FIG. 1 taken along line IV-IV of FIG. 3. [Diagram 5] FIG. 4 is a radial cross-sectional view of the tool holder taken along line VV of FIG. 3. [Figure 5a] FIG. 6 is a detailed view of FIG. 5. [Figure 6] FIG. 4 is a first detailed view of FIG. 3. [Figure 7] FIG. 4 is a second detailed view of FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] 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, dimensions of some of the elements may be exaggerated relative to other elements for clarity or several physical components may be contained within a single functional block or element. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.

[0011] In the following description, various aspects of the subject matter of the present application are described. For purposes of explanation, specific configurations and details are shown in sufficient detail to provide a thorough understanding of the subject matter of the present application. However, it will be apparent to one skilled in the art that the subject matter of the present application may be practiced without the specific configurations and details presented herein.

[0012] Attention is first directed to FIG. 1 , which illustrates a cutting tool 20 for chip removal according to one aspect of the present application. The cutting tool 20 has a tool longitudinal axis A. According to some embodiments of the present subject matter, the cutting tool 20 may be a fixed cutting tool. That is, the cutting tool 20 is not designed to rotate about an axis of rotation. In the illustrated non-limiting example, the cutting tool 20 is a boring bar. However, the present subject matter is not limited to boring bars, and may be applicable to turning tools in general, for example, but not limited to. The present subject matter may also be applicable to rotary cutting tools, such as milling cutters and drills. For such rotary cutting tools, the cutting tool 20 is designed to be rotatable in a rotational direction about the tool longitudinal axis A.

[0013] The cutting tool 20 includes a tool holder 22. The cutting tool 20 also includes a cutting portion 24 that may include at least one cutting insert 26. The at least one cutting insert 26 is designed to perform a metal cutting operation and has a cutting edge for this purpose. According to some embodiments of the present subject matter, the 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, as seen in the illustrated non-limiting example, the cutting portion 24 may be releasably attached to the tool holder 22. The cutting portion 24 may be disposed at a front end of the tool holder 22. The rear end of the tool holder 22 is configured to be secured by a retention device.

[0014] 2, which shows an exploded view of a tool holder 22 according to another embodiment of the present invention. F and backward D RThe tool holder 22 has a holder longitudinal axis B that defines a center axis B. The tool holder 22 is elongated along the holder longitudinal axis B. According to some embodiments of the present subject matter, the cutting tool 20 and the tool holder 22 may be coaxial with one another. It is noted that two elements (e.g., the cutting tool 20 and the tool holder 22 in this case) are coaxial with one another if their longitudinal axes coincide (are aligned with one another).

[0015] It should be further noted that use of the terms "forward" and "rearward" throughout this specification and claims refers to relative positions toward the left and right, respectively, in FIG. 3 in the direction of the holder longitudinal axis B. Generally, the forward direction is toward the cutting portion 24.

[0016] 3, the toolholder 22 includes a toolholder coolant passageway 28 having an external coolant inlet 30 and an external coolant outlet 32. The coolant inlet 30 and outlet 32 ​​are in fluid communication with one another. Coolant travels through the toolholder 22 and along a coolant flow path F (indicated by arrows in the figures) through the toolholder coolant passageway 28. It should be noted that use of the term "external inlet / outlet" throughout this specification and claims refers to an opening located on the outer periphery of the toolholder 22. Additionally, it should be noted that use of the term "internal inlet / outlet" throughout this specification and claims refers to an opening located on the interior of the toolholder 22.

[0017] As best shown in FIGS. 1 and 2, the tool holder 22 includes an outer sleeve 74. The outer sleeve 74 includes opposed forward and rearward sleeve end faces 76a, 76b and a sleeve circumferential surface 78 extending between the forward and rearward sleeve end faces 76a, 76b. The outer sleeve 74 further includes a sleeve bore 80. The sleeve bore 80 has a sleeve bore wall 82 that opens into the forward sleeve end face 76a. According to some embodiments of the present subject matter, the sleeve bore wall 82 may open into the rearward sleeve end face 76b. In such a configuration, the sleeve bore 80 forms a through hole. According to some other embodiments of the present subject matter, the sleeve bore wall 82 may not open into the rearward sleeve end face 76b. In such a configuration, the sleeve bore 80 forms a blind hole. The sleeve bore wall 82 may have a cylindrical shape. In the assembled cutting tool 20, the sleeve bore 80 may extend along the tool longitudinal axis A.

[0018] According to some embodiments of the present subject matter, the outer sleeve 74 may include a forward outer sleeve component 74a and a rearward outer sleeve component 74b. The forward outer sleeve component 74a and the rearward outer sleeve component 74b may be fixedly engaged with one another. The forward outer sleeve component 74a is forward of the rearward outer sleeve component 74b. It is noted that the sleeve bore 80 may be formed from a through hole in the forward outer sleeve component 74a and a blind hole in the rearward outer sleeve component 74b, or a through hole in both the forward outer sleeve component 74a and the rearward outer sleeve component 74b. The forward outer sleeve component 74a may be longer than the rearward outer sleeve component 74b as measured between the forward sleeve end face 76a and the rearward sleeve end face 76b.

[0019] The outer sleeve 74 includes a sleeve material, which according to some embodiments of the present subject matter may be a carbide.

[0020] The tool holder 22 also includes a mass housing portion 40. The mass housing portion 40 includes opposed front and rear housing end faces 41 a, 41 b, and a housing perimeter surface 39 extending between the front and rear housing end faces 41 a, 41 b. In the assembled tool holder 22, the housing perimeter surface 39 extends about the holder longitudinal axis B.

[0021] According to some embodiments of the present subject matter, mass housing portion 40 can include a housing recess 84. Housing recess 84 can include an inwardly facing recess wall 86. Recess wall 86 can open to rear housing end surface 41b.

[0022] According to some embodiments of the present subject matter, the mass housing portion 40 can include a forward housing portion 40a and a rearward housing portion 40b. The forward housing portion 40a can be located forward of the rearward housing portion 40b. The forward housing portion 40a can have a larger radial dimension than the rearward housing portion 40b. The forward housing portion 40a is configured to have a cutting portion 24 secured thereto. To this end, in this illustrated non-limiting example, the forward housing end surface 41a is serrated to engage a corresponding surface of the cutting portion 26.

[0023] According to some embodiments of the subject matter of the present application, the housing outer periphery 39 may include a front housing outer periphery 39a at the front housing portion 40a and a rear housing outer periphery 39b at the rear housing portion 40b. The housing outer periphery 39 may include a housing step surface 39s connecting the front housing outer periphery 39a and the rear housing outer periphery 39b. The housing step surface 39s is preferably oriented perpendicular to the holder longitudinal axis B and is oriented in a rearward direction D. R may be faced with

[0024] 6, according to some embodiments of the present subject matter, the front housing portion 40a may include a front housing coolant passage 88 that may open at its rear end into the housing step surface 39s. The front housing coolant passage 88 may further open at its front end into the housing outer periphery 39 or the front housing outer periphery 39a, or into the intersection of the housing outer periphery 39 and the front housing outer periphery 39a to form a coolant outlet 32.

[0025] With reference to FIG. 7, according to some embodiments of the present subject matter, rear housing portion 40b can include a rear housing coolant passageway 90 that can open to recess wall surface 86 and rear housing outer periphery surface 39b.

[0026] According to some embodiments of the subject matter of the present application, the rear housing outer circumferential surface 39b may include a front rear housing outer circumferential surface 39b-a and a rear rear housing outer circumferential surface 39b-b that are axially spaced apart from each other along the holder longitudinal axis B. The front rear housing outer circumferential surface 39b-a is closer to the front housing portion 40a than the rear rear housing outer circumferential surface 39b-b. The front rear housing outer circumferential surface 39b-a may intersect the housing step surface 39s. The front rear housing outer circumferential surface 39b-a and the rear rear housing outer circumferential surface 39b-b may have a cylindrical shape. The rear housing outer circumferential surface 39b may include an intermediate rear housing outer circumferential surface 39b-c that extends between the front rear housing outer circumferential surface 39b-a and the rear rear housing outer circumferential surface 39b-b. The intermediate rear housing outer circumferential surface 39b-c may be radially recessed relative to the front rear housing outer circumferential surface 39b-a and the rear rear housing outer circumferential surface 39b-b. That is, the intermediate rear housing outer circumferential surface 39b-c may form an annular recess and, therefore, may have a maximum radial cross-section that is smaller than the maximum radial cross-sections of both the front rear housing outer circumferential surface 39b-a and the rear rear housing outer circumferential surface 39b-b.

[0027] Mass housing portion 40 includes the housing body material. According to some embodiments of the present subject matter, the sleeve material may be denser than the housing body material.

[0028] The tool holder 22 includes an elongated groove 92 formed in one of the housing outer periphery 39 and the sleeve bore wall 82. That is, the elongated groove 92 is recessed into one of the housing outer periphery 39 and the sleeve bore wall 82. According to some embodiments of the present subject matter, the groove 92 may be formed in the housing outer periphery 39.

[0029] The groove 92 has two opposite groove ends 94a, 94b. One of the two groove ends 94a may be located at the rear housing outer peripheral surface 39b-b. The other of the two groove ends 94a may be located at the intersection of the front housing outer peripheral surface 39b-a and the housing step surface 39s. The groove 92 extends along a groove axis G. According to some embodiments of the subject matter of the present application, the groove 92 may extend linearly along the groove axis G.

[0030] 5a, according to some embodiments of the present subject matter, the groove 92 may include two opposing groove sides 95 located on either side of a half-plane HP that includes the holder longitudinal axis B and the groove axis G, and a groove base surface 93 extending between the two opposing groove sides 95. The groove base surface 93 may extend along the groove axis G. The groove 92 may have a groove depth GD measured in a radially inward direction from a circumferential center of the groove base surface 93. The groove depth GD may be between 1 mm and 2 mm. The groove 92 may have a groove width GW measured in a direction between the two opposing groove sides 95. The groove width GW may be between 3 mm and 4 mm.

[0031] The tool holder 22 includes a vibration isolator 34. The tool vibration isolator 34 is designed to reduce or eliminate vibrations of the cutting tool 20 as the cutting tool 20 performs a metal cutting operation. According to some embodiments of the present subject matter, the vibration isolator 34 may be disposed at a front end of the cutting tool 20.

[0032] The mass housing portion 40 has an internal holder cavity 36 formed therein. That is, the internal holder cavity 36 is enclosed within the mass housing portion 40. The holder cavity 36 is defined, at least in part, by an inwardly facing cavity wall 38. The cavity wall 38 defines 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. According to some embodiments of the present subject matter, the holder cavity 36 may be elongated along the cavity central axis D. The holder cavity 36 may be elongated in the same direction as the tool holder 22. In particular, the holder cavity 36 may be coaxial with the tool holder 22. The cavity wall 38 may include two opposing cavity wall end faces 42 and a cavity wall circumferential surface 44 extending between the cavity wall end faces 42. The cavity wall perimeter surface 44 may extend about the central cavity axis D.

[0033] 3 , which shows an axial cross-sectional view of the holder cavity 36 (taken in a plane including the cavity central axis D) through the cavity wall outer periphery 44, the holder cavity 36 has a cavity cross-section. According to some embodiments of the present subject matter, the cavity cross-section may be uniform along the cavity central axis D. The cavity wall outer periphery 44 may have a generally cylindrical shape. The cavity wall outer periphery 44 may have a cylindrical shape near the two cavity wall end faces 42. The two cavity wall end faces 42 may be flat and oriented transversely to the cavity central axis D. The two cavity wall end faces 42 may be oriented perpendicular to the cavity central axis D.

[0034] 1 and 2, the tool holder 22 of the present invention also includes a vibration isolation device 34 that includes at least one vibration absorbing mass 54. According to some embodiments of the present subject matter, the vibration absorbing mass 54 may be rigid. In some embodiments, the mass housing portion 40 may be formed from a first metallic material, such as steel, and the vibration absorbing mass 54 may be formed from a second, more dense metallic material, such as tungsten.

[0035] 2-3, the vibration absorbing mass 54 has a mass central axis E. The vibration absorbing mass 54 includes two axially opposed mass ends 60a, 60b, a forward mass end 60a and a rearward mass end 60b, with the forward mass end 60a being forward of the rearward mass end 60b. The two axially opposed mass ends 60a, 60b are spaced apart from one another along the mass central axis E. According to some embodiments of the subject matter of the present application, the vibration absorbing mass 54 may include two opposed mass end faces 56 and a mass perimeter surface 58 extending between the mass end faces 56. The mass perimeter surface 58 may extend about the mass central axis E. The two mass end faces 56 are located at the two mass ends 60a, 60b, respectively. The vibration absorbing mass 54 may be elongated along the mass central axis E. The vibration absorbing mass 54 may have a substantially constant cross-sectional area between the mass end faces 56 in a plane oriented perpendicular to the mass central axis E.

[0036] 3, according to some embodiments of the present subject matter, the mass end surface 56 may be conical in shape, tapering inwardly in a direction away from the central portion of the vibration absorbing mass 54. The mass outer periphery surface 58 may have a cylindrical shape.

[0037] The vibration isolation device 34 further includes two elastic suspension members 62. The two suspension members 62 are elastically deformable. According to some embodiments of the present subject matter, the two suspension members 62 may be formed from a material different from the material of the vibration absorbing mass 54. In some embodiments, the suspension members 62 are made from rubber having a durometer hardness between 60A and 95A. The two suspension members 62 may be O-rings.

[0038] 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 of the inner holder cavity 36 and / or the mass housing portion 40 is not secured to the outer sleeve 74.

[0039] According to some embodiments of the present subject matter, and referring to FIG. 3, the tool holder 22 includes a hollow axial seal member 67 that is axially spaced from the tool holder 22 in the rearward direction D. R defines (defines) the holder cavity 36 and seals the holder cavity 36. That is, the cavity axial sealing member 67 forms one of the cavity wall end faces 38. While the holder cavity 36 is not sealed by the cavity axial sealing member 67 (i.e., while the tool holder 22 is in the unassembled position), the vibration absorbing mass 54 may be inserted into the holder cavity 36.

[0040] In the assembled condition of the tool holder 22 , the vibration absorbing mass 54 is disposed within the holder cavity 36 .

[0041] In the assembled position with the tool holder 22, according to some embodiments of the present subject matter, the vibration absorbing mass 54 may be elongated in the same direction as the tool holder 22. That is, the mass central axis E may be parallel to the holder longitudinal axis B, along with axes B, E, which establish the longest major dimension of the tool holder 22 and the vibration absorbing mass 54, respectively. In particular, the mass central axis E may be coincident with the holder longitudinal axis B (i.e., the vibration absorbing mass 54 may be coaxial with the tool holder 22).

[0042] In the assembled position of the tool holder 22, the vibration absorbing mass 54 is connected to the mass housing portion 40 via two suspension members 62. The vibration absorbing mass 54 is thus elastically suspended within the holder cavity 36 by the two suspension members 62 in contact with the inwardly facing cavity wall surface 38. Each suspension member 62 may abut a respective mass end face 56. It should be noted that no portion of the mass outer circumferential surface 58 is in direct contact with the inwardly facing cavity wall surface 38. According to some embodiments of the present subject matter, each of the two suspension members 62 may be under compressive elastic deformation by contact against the inwardly facing cavity wall surface 38 and against one of the mass end faces 56.

[0043] In the assembled state of the tool holder 22, the mass housing portion 40 is at least partially located within the sleeve bore 80. According to some embodiments of the present subject matter, only the rear housing portion 40b may be located within the sleeve bore 80. The sleeve outer circumferential surface 78 extends about the holder longitudinal axis B.

[0044] At least a portion of the sleeve hole wall 82 surrounds at least a portion of the mass housing portion 40. More specifically, at least a portion of the sleeve hole wall 82 faces a portion of the outer housing surface 39 along a common interface. And more specifically, at the common interface, at least a portion of the sleeve hole wall 82 faces the rear outer housing surface 39b.

[0045] According to some embodiments of the present subject matter, the front rear housing outer circumferential surface 39b-a, the rear rear housing outer circumferential surface 39b-b, and the intermediate rear housing outer circumferential surface 39b-c may all abut the sleeve bore wall surface 82 at the common interface. Alternatively, according to some embodiments of the present subject matter, some portions of the rear housing outer circumferential surface 39 may not abut the sleeve bore wall surface 82 at the common interface. For example, the front rear housing outer circumferential surface 39b-a and the rear rear housing outer circumferential surface 39b-b may abut the sleeve bore wall surface 82, while the intermediate rear housing outer circumferential surface 39b-c may be spaced from the sleeve bore wall surface 82 by a distance d (e.g., in a configuration in which the intermediate rear housing outer circumferential surface 39b-c is recessed relative to the front rear housing outer circumferential surface 39b-a and the rear rear housing outer circumferential surface 39b-b; see FIG. 5). This latter configuration is easier to manufacture than the former configuration. The front sleeve end surface 76a and the housing step surface 39s may abut each other. According to some embodiments of the present subject matter, a shrink fit engagement is preferably used to connect the (heated) outer sleeve 74 and the mass housing portion 40. Additionally, the forward sleeve end surface 76a and the housing step surface 39s may be fixedly brazed together.

[0046] The grooves 92 are at a common interface to form a groove coolant passage 96. The toolholder coolant passage 28 is partially defined by the groove coolant passage 96. That is, the groove coolant passage 96 is a part of the toolholder coolant passage 28. The groove coolant passage 96 includes a groove coolant wall 97. The groove coolant wall 97 extends about a groove axis G. The groove coolant passage 96 has a groove coolant inlet 98 and a groove coolant outlet 100. According to some embodiments of the present subject matter, the groove coolant inlet 98 and / or the groove coolant outlet 100 may be internal. The groove coolant inlet 98 may be located at one of the two groove ends 94b, and the groove coolant outlet 100 may be located at the other of the two groove ends 94a. The groove axis G may be parallel to the holder longitudinal axis B.

[0047] In a configuration in which the front rear housing outer peripheral surface 39b-a, the rear rear housing outer peripheral surface 39b-b and the intermediate rear housing outer peripheral surface 39b-c all abut the sleeve hole wall surface 82, the groove coolant wall surface 97 is formed by the groove 92 (i.e., the groove base surface 93 and the two groove side surfaces 95), and no groove 92 is formed in the opposing portion of either the housing outer peripheral surface 39 or the sleeve hole wall surface 82.

[0048] In the configuration where the intermediate rear housing outer circumferential surface 39b-c is spaced from the sleeve hole wall surface 82, the groove coolant wall surface 97 is formed as described in the previous paragraph and is also formed by a thin annular gap AG formed between the spaced intermediate rear housing outer circumferential surface 39b-c and the sleeve hole wall surface 82, which merges with the groove 92 in the circumferential direction (FIG. 5). It should be noted that the volume defined by the thin annular gap AG is negligible. For example, the distance d may have a value that ensures that the flow of coolant along the groove coolant passage 96 is not adversely affected. For example, even if coolant may seep into the annular gap AG, high pressure coolant flow may still be achieved. The distance d may be 0.07 mm or less. More preferably, the distance d may be 0.05 mm or less.

[0049] According to some embodiments of the present subject matter, the groove coolant passages 96 may extend into the front housing coolant passages 88. Thus, it should be noted that in configurations in which the grooves 92 are formed in the housing perimeter surface 39, the grooves 92 extend into the front housing coolant passages 88. The tool holder coolant passages 28 may be further defined in part by the front housing coolant passages 88. That is, the front housing coolant passages 88 are part of the tool holder coolant passages 28.

[0050] According to some embodiments of the present subject matter, the hollow axial sealing member 67 can be located within the housing recess 84 and can be axially spaced apart in the rearward direction D R 4 defines the holder cavity 36. The forward portion of the housing recess 84 thus defines the inner holder cavity 36. The rear housing coolant passage 90 may be rearward of the cavity axial sealing member 67. The toolholder coolant passage 28 may be further partially defined by the rear housing coolant passage 90. That is, the rear housing coolant passage 90 is part of the toolholder coolant passage 28.

[0051] According to some embodiments of the present subject matter, the recess wall 86 may open to the rear housing end face 41 b to form the coolant inlet 30. The toolholder coolant passage 28 may be further defined in part by a portion of the housing recess 84 that extends from the coolant inlet 30. That is, the portion of the housing recess 84 that extends from the coolant inlet 30 is part of the toolholder coolant passage 28.

[0052] According to some embodiments of the present subject matter, the coolant outlet 32 ​​may be rotationally aligned with the cutting insert 26 about the holder longitudinal axis B. This allows for the directing of coolant at the cutting interface between the cutting edge and the workpiece.

[0053] The vibration isolation device 34 includes an oscillation space 68 formed within the holder cavity 36. The oscillation space 68 is located between the vibration absorbing mass 54 and the mass housing portion 40 (more specifically, between the vibration absorbing mass 54 and the inward-facing cavity wall surface 38). In other words, the mass housing portion 40 and the vibration absorbing mass 54 are separated by the oscillation space 68. According to some embodiments of the present subject matter, the oscillation space 68 completely surrounds the vibration absorbing mass 54 in the circumferential direction. That is, the oscillation space 68 may extend around the full (360°) angular extent of the cavity central axis D. Thus, the oscillation space 68 may be considered an annular oscillation space that surrounds the axial extent of the vibration absorbing mass 54.

[0054] The vibration absorbing mass 54 is configured to oscillate in the oscillation space 68 under elastic deformation of the two suspension members 62. In other words, the vibration absorbing mass 54 oscillates and is displaceable in the oscillation space 68 when the two suspension members 62 are subjected to elastic deformation.

[0055] The cutting tool 20 is subject to vibrations when confronted with a workpiece. Typically, for turning or milling cutting operations, the vibrations are lateral. Typically, for drilling cutting operations, the vibrations are torsional. The vibration absorbing mass 54 oscillates at a certain frequency. The vibration isolator 34 is designed to provide the vibration absorbing mass 54 with a frequency that is close to, if not the same as, the natural frequency of the cutting tool 20, thereby reducing or eliminating the vibration of the cutting tool 20.

[0056] Advantageously, the vibration isolator 34 may be adjustable (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 may be used, alone or in combination, to modify the frequency at which the vibration absorbing mass 54 oscillates. In one non-limiting example, at least two suspension members 62 may be preloaded. For example, referring to FIG. 3, the vibration isolator 34 may include an adjustment member 70 that protrudes into the oscillation space 68. The adjustment member 70 may be a screw having a threaded portion 72 (see FIG. 7). The adjustment member 70 may abut against the cavity axial sealing member 67. The adjustment member 70 may be displaceable along the cavity central axis D, thereby displacing the cavity axial sealing member 67 as well, thereby adjusting the elastic properties of the two suspension members 62. According to some embodiments of the subject matter of the present application, the oscillation space 68 may be empty. For example, the oscillation space 68 may be free of viscous fluid.

[0057] It should be noted that one feature of the inventive configuration is that the toolholder coolant passages 28 are separated from the vibration isolator 34. In other words, the toolholder coolant passages 28 are not in fluid communication with the vibration absorbing mass 54. As a result of such configuration, there is no possibility of leakage of coolant from the toolholder coolant passages 28 in the vicinity of the holder cavity 36 in which the vibration absorbing mass 54 is located. Thus, leakage of coolant does not interfere with the vibration damping effect of the vibration isolator 34.

[0058] A further feature of the inventive arrangement is that it has no tubes (as disclosed in US 7,681,869) that interfere with the oscillation of the vibration absorbing mass 54. Furthermore, the vibration absorbing mass 54 is solid in the sense that it has no hollow portions (e.g., to receive tubes), reducing the weight of the vibration absorbing mass 54 itself.

[0059] Although the subject matter of the present application has been described in some detail, it should be understood that various changes and modifications can be made without departing from the spirit or scope of the invention as hereinafter claimed.

[0060] For example, the groove coolant passage 96 may be formed from grooves formed in both the housing outer periphery 39 and the sleeve bore wall 82, respectively, with the two grooves facing each other in the assembled tool holder.

[0061] Further, for example, the tool holder 22 may include two or more coolant passages 96. Still further, for example, the vibration isolator 34 may include two or more vibration absorbing masses 54. In this non-limiting example shown, the vibration isolator 34 includes two vibration absorbing masses 54a, 54b that are elastically connected by two central suspension members 63 (e.g. O-rings), while the above-mentioned elastic suspension members 62 support end faces 56 belonging to the two different vibration absorbing masses.

Claims

1. Opposite forward direction (D Ｆ ) and a rear direction (D Ｒ ), an elongated tool holder (22) along a holder longitudinal axis (B) defining), the tool holder (22) is configured to have a cutting portion (24) fixed to the front end of the tool holder (22), the tool holder (22) is, An outer sleeve (74), comprising: opposite front sleeve end faces (76a) and rear sleeve end faces (76b), a sleeve outer peripheral surface (78) extending between the front sleeve end face (76a) and the rear sleeve end face (76b), and a sleeve hole (80) having a sleeve hole wall surface (82) opening into the front sleeve end face (76a) and the rear sleeve end face (76b). An outer sleeve (74); A mass body housing portion (40), comprising: opposite front housing end faces (41a) and rear housing end faces (41b), a housing outer peripheral surface (39) extending between the front housing end face (41a) and the rear housing end face (41b), and an internal holder cavity (36) having an inward-facing cavity wall surface (38). A mass body housing portion (40); A vibration isolation device (34), comprising: a vibration absorption mass body (54) having two opposite mass body end faces (56) and a mass body outer peripheral surface (58) extending between the mass body end faces (56). A vibration isolation device (34); Two elastic suspension members (62); and An elongated groove (92) is formed in one of the housing outer peripheral surface (39) and the sleeve hole wall surface (82). The tool holder (22) is adjustable between a non-assembled state and an assembled state. In the assembled state: the vibration absorption mass body (54) is disposed within the internal holder cavity (36) and is elastically suspended within the internal holder cavity (36) by the two suspension members (62) that contact the inward-facing cavity wall surface (38); the mass body housing portion (40) is at least partially located within the sleeve hole (80), and at least a portion of the sleeve hole wall surface (82) surrounds at least a portion of the housing outer peripheral surface (39) about the holder longitudinal axis (B), thereby defining a common interface; the groove (92) is located at the common interface, thereby forming a groove coolant passage (96); The groove coolant passage (96) is part of a tool holder coolant passage (28) having an external coolant inlet (30) and an external coolant outlet (32) that are in fluid communication with each other. A tool holder (22).

2. The groove (92) is formed within the housing outer peripheral surface (39). The tool holder (22) according to Claim 1.

3. The sleeve hole wall surface (82) opens into the rear sleeve end face (76b). The tool holder (22) according to Claim 1.

4. The groove (92) linearly extends along a groove axis (G), In an assembled state of the tool holder (22), the groove axis (G) is parallel to the holder longitudinal axis (B). The tool holder (22) according to claim 1.

5. The mass body housing part (40) includes a front housing part (40a) and a rear housing part (40b). The front housing part (40a) is in front of the rear housing part (40b) and has a larger radial dimension than the rear housing part (40b). In an assembled state of the tool holder (22), only the rear housing part (40b) is located within the sleeve hole (80). The tool holder (22) according to claim 1.

6. The outer peripheral surface (39) of the housing has a front housing outer peripheral surface (39a) on the front housing part (40a), a rear housing outer peripheral surface (39b) on the rear housing part (40b), and a housing step surface (39s) connecting the front housing outer peripheral surface (39a) and the rear housing outer peripheral surface (39b). It is provided with The front housing part (40a) has a front housing coolant passage (88) opening to the housing step surface (39s) at the rear end of the front housing part (40a). In an assembled state of the tool holder (22), the groove coolant passage (96) extends to the front housing coolant passage (88). The front housing coolant passage (88) is a part of the tool holder coolant passage (28). The tool holder (22) according to claim 5.

7. The front housing coolant passage (88) further opens to the outer peripheral surface (39) of the housing at the front end of the front housing part (40a) so as to form the coolant outlet (32). The tool holder (22) according to claim 6.

8. The mass body housing part (40) has a housing recess (84). The housing recess (84) has an inward recess wall surface (86) opening to the rear housing end face (41b). The tool holder (22) has an axial cavity sealing member (67). In the assembled state of the tool holder (22), the cavity axial direction sealing member (67) is located within the housing recess (84), and in the rearward direction (D Ｒ ) defines the range of the holder cavity (36), such that the front portion of the housing recess (84) forms the internal holder cavity (36). The rear housing part (40b) has a rear housing coolant passage (90) opening to the recess wall surface (86) and the rear housing outer peripheral surface (39b). In an assembled state of the tool holder (22), the rear housing coolant passage (90) is behind the axial cavity sealing member (67). The rear housing coolant passage (90) is a part of the tool holder coolant passage (28). The tool holder (22) according to claim 6.

9. The outer sleeve (74) includes a front outer sleeve component (74a) and a rear outer sleeve component (74b), the front outer sleeve component (74a) and the rear outer sleeve component (74b) are fixedly engaged with each other, and the front outer sleeve component (74a) is in front of the rear outer sleeve component (74b), the tool holder (22) according to claim 8. **Claim 10** In the assembled state of the tool holder (22), the front sleeve end face (76a) and the housing step face (39s) are in contact with each other, the tool holder (22) according to claim 6. **Claim 11** The outer peripheral surface of the rear housing (39b) includes a previous outer peripheral surface of the rear housing (39b-a) and a subsequent outer peripheral surface of the rear housing (39b-b) that are axially spaced apart, and an intermediate rear outer peripheral surface (39b-c) that extends between the previous outer peripheral surface of the rear housing (39b-a) and the subsequent outer peripheral surface of the rear housing (39b-b), and the previous outer peripheral surface of the rear housing (39b-a) is closer to the front housing portion (40a) than the subsequent outer peripheral surface of the rear housing (39b-b), In the assembled state of the tool holder (22), at least the previous outer peripheral surface of the rear housing (39b-a) and the subsequent outer peripheral surface of the rear housing (39b-b) are in contact with the sleeve hole wall surface (82) respectively, the tool holder (22) according to claim 6. **Claim 12** The groove (92) is formed in the outer peripheral surface of the housing (39), the groove (92) includes two groove end portions (94a, 94b), the previous outer peripheral surface of the rear housing (39b-a) intersects the housing step face (39s), one of the two groove end portions (94b) is located on the subsequent outer peripheral surface of the rear housing (39b-b), the other of the two groove end portions (94a) is located on the intersection line between the previous outer peripheral surface of the rear housing (39b-a) and the housing step face (39s), the tool holder (22) according to claim 11. **Claim 13** The intermediate rear outer peripheral surface (39b-c) is recessed radially with respect to the previous outer peripheral surface of the rear housing (39b-a) and the subsequent outer peripheral surface of the rear housing (39b-b), In the assembled state of the tool holder (22), the intermediate rear outer peripheral surface (39b-c) is spaced apart from the sleeve hole wall surface (82), the tool holder (22) according to claim 11. **Claim 14** The mass body housing portion (40) includes a housing recess (84), and the housing recess (84) includes an inwardly concave wall surface (86) that opens to the rear housing end face (41b). The tool holder (22) includes a cavity axial direction sealing member (67). In the assembled state of the tool holder (22), the cavity axial direction sealing member (67) is located within the housing recess (84), and defines the range of the holder cavity (36) in the rearward direction (D Ｒ ) such that the front portion of the housing recess (84) forms the internal holder cavity (36). The tool holder (22) according to claim 1.

15. In the assembled state of the tool holder (22), the concave wall surface (86) opens to the rear housing end face (41b) so as to form the coolant inlet (30). The tool holder (22) according to claim 14, wherein a part of the housing recess (84) extending from the coolant inlet (30) is a part of the tool holder coolant passage (28).

16. The outer sleeve (74) includes a sleeve material. The mass body housing portion (40) includes a housing body material. The tool holder (22) according to claim 1, wherein the sleeve material is denser than the housing body material.

17. The tool holder (22) according to claim 16, wherein the sleeve material is carbide.

18. A cutting tool (20) comprising the tool holder (22) according to claim 1, and a cutting portion (24) located at the front end of the tool holder (22). The cutting portion (24) includes at least one cutting insert (26).

19. The cutting tool (20) according to claim 18, wherein the cutting portion (24) is detachably attached to the tool holder (22).

20. The cutting tool (20) according to claim 18, wherein the coolant outlet (32) is rotationally aligned with the cutting insert (26) around the holder longitudinal axis (B).

Images