(19)
(11)EP 2 276 597 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
04.01.2017 Bulletin 2017/01

(21)Application number: 09743543.2

(22)Date of filing:  06.05.2009
(51)International Patent Classification (IPC): 
B23B 31/06(2006.01)
B23B 31/00(2006.01)
B23B 31/07(2006.01)
B23B 31/10(2006.01)
B23Q 3/12(2006.01)
(86)International application number:
PCT/US2009/042953
(87)International publication number:
WO 2009/137557 (12.11.2009 Gazette  2009/46)

(54)

TOOL HOLDER WITH BALL CLAMPING MECHANISM

WERKZEUGHALTER MIT KUGELKLEMMMECHANISMUS

PORTE-OUTIL AVEC MÉCANISME DE SERRAGE À BILLE


(84)Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK TR

(30)Priority: 09.05.2008 US 118048

(43)Date of publication of application:
26.01.2011 Bulletin 2011/04

(73)Proprietors:
  • KENNAMETAL INC.
    Latrobe, PA 15650 (US)
  • Erickson, Carla
    Raleigh NC 27609-6032 (US)

(72)Inventor:
  • ERICKSON, Robert, A
    . (US)

(74)Representative: Prinz & Partner mbB 
Patent- und Rechtsanwälte Rundfunkplatz 2
80335 München
80335 München (DE)


(56)References cited: : 
EP-A2- 1 543 904
JP-A- 2002 326 105
US-A- 2 485 799
US-A- 5 697 740
US-B1- 7 284 938
WO-A1-94/05450
JP-U- H0 636 706
US-A- 2 684 249
US-A- 5 926 931
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description


    [0001] The invention relates to a tool holder with a clamping mechanism, and in particular to a tool clamping mechanism having two clamping jaws connected by a double-ended screw and held in an axial location by slots in the tool holder body.

    [0002] Coupling systems for interconnecting machine tools are well known in the prior art. Such coupling systems include a hollow, frustro-conical male component that forms part of the tool which mates with a frustro-conical opening in a female component. The female component is typically part of a spindle for rotating the tool, The taper of both the frustro-conical components often has a slope of about 1 to 10 with respect to the longitudinal axis of the tool. Such a slope provides a rigid, on-center interference coupling when the components are pulled together by means of a clamping mechanism disposed in the interior of the female opening.

    [0003] There are presently a variety of mechanisms for clamping together the frustro-conical male and female components of prior art coupling systems. In some of these mechanisms, the female component on the toolholder includes radially movable locking balls for engaging complementarily-shaped socket openings in the walls of the male component. When moved radially outwardly, the locking balls function to secure and pull in the frustro- conical tool shank into the frustro-conical opening in the toolholder. An axially slidable bolt having cam surfaces radially forces the locking balls outwardly into the socket openings. In other types of mechanisms, the female opening includes a radially expandable locking plunger which is extendable into the hollow interior of the frustro-conical male component. The locking plunger may include two or more radially movable fingers that engage openings in the wall of the frustro-conical ly shaped male component in order to forcefully wedge the male component of the tool into the female component of the toolholder.

    [0004] US 2 684 249 discloses a toolholder in accordance with the preamble of claim 1 comprising a tool head connected to a holder body via a clamping mechanism. The tool head has a retention knob located at a tampered end thereof, which is adapted to engage with the clamping mechanism when mounted. The mechanism comprises peripherally spaced cam members which are radially moveable within the holder body in order to contact frusto-conical cam surfaces of the tool head in a wedge camming engagement.

    [0005] While both of these general types of prior art coupling systems have shown themselves to be effective for their intended purpose, conventional coupling systems tend to put force on the body and possibly cause misalignment between the cutting head and the body, particularly for small cutters. Therefore, it would be desirable to design a coupling system that minimizes force on the body, and therefore minimizing misalignment between the cutting head and the body.

    BRIEF SUMMARY OF THE INVENTION



    [0006] According to the present invention, a tool holder is provided as defined in claim 1, The tool holder comprises a body having a ball clamping mechanism aperture; a cutting head having a cutting end portion, a tapered end portion, and a middle portion located between the cutting end and the tapered end portion; a retention knob located at the tapered end portion of the cutting head, the retention knob including a generally spherical end portion at least partially disposed within the body, the generally spherical end portion including an upper spherical clamp surface and a lower spherical clamp surface; and a ball clamping mechanism received in the ball clamping mechanism aperture of the body. The ball clamping mechanism comprises an upper clamp having an upper clamp cavity capable of receiving the generally spherical end portion of the retention knob, the upper clamp cavity including a generally spherical upper clamp cavity portion and a generally cylindrical upper clamp cavity portion, a portion of the generally cylindrical upper clamp cavity portion defining a generally cylindrical upper clamp surface; a lower clamp having a lower clamp cavity capable of receiving the generally spherical end portion of the retention knob, the lower clamp cavity including a generally spherical lower clamp cavity portion and a generally cylindrical lower clamp cavity portion, a portion of the generally cylindrical lower clamp cavity portion defining a generally cylindrical lower clamp surface; and a double-ended clamp screw for threadingly receiving the upper and lower clamps. Rotation of the double-ended clamp screw in a first direction causes the generally cylindrical upper and lower clamp surfaces of the upper and lower clamps to move toward each other and engage the generally spherical upper and lower spherical clamp surfaces of the retention knob, respectively. The generally cylindrical upper and lower contact surfaces elastically deform during engagement with the generally spherical upper and lower clamp surfaces of the retention knob to form a lenticular contact area and securely hold the cutting head in face contact with the body and place the tool holder in a locked position,

    [0007] In another embodiment, the double-ended clamp screw includes a middle portion disposed within the slot of the retention knob.

    [0008] These and other aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

    FIGURE 1 is a cross- sectional view of a tool holder with a ball clamping mechanism in the locked position according to an embodiment of the invention;

    FIGURE 2 is an enlarged view of the ball clamping mechanism of FIG. 1 in the locked position;

    FIGURE 3 is a cross-sectional view of the tool holder with the ball clamping mechanism of FIG, 1 in the unlocked position;

    FIGURE 4 is an enlarged view of the ball clamping mechanism of FIG. 3 in the unlocked position;

    FIGURE 5 is a perspective view of a body of the tool holder of FIG. 1 according to an embodiment of the invention;

    FIGURE 6 is a top view of the body of the tool holder of FIG. 5;

    FIGURE 7 is a cross- sectional view of the body taken along line 7-7 of FIG. 6;

    FIGURE 8 is a perspective view of a cutting head of the tool holder of FIG. 1 according to an embodiment of the invention;

    FIGURE 9 is a side view of the cutting head of FIG. 8;

    FIGURE 10 is a cross-sectional view of the cutting head taken along line 10-10 of FIG. 9;

    FIGURE 11 is a side view of a retention knob of the tool holder of FIG. 1 according to an embodiment of the invention;

    FIGURE 12 is a perspective of an upper clamp of the tool holder of FIG. 1 according to an embodiment of the invention;

    FIGURE 13 is a top view of the upper clamp of FIG. 12;

    FIGURE 14 is an end view of the upper clamp of FIG. 12;

    FIGURE 15 is a bottom view of the upper clamp of FIG. 12;

    FIGURE 16 is a cross-sectional view of the upper clamp taken along line 16-16 of FIG. 15;

    FIGURE 17 is a perspective of a lower clamp of the tool holder of FIG. 1 according to an embodiment of the invention;

    FIGURE 18 is a bottom view of the lower clamp of FIG. 17;

    FIGURE 19 is an end view of the lower clamp of FIG. 17;

    FIGURE 20 is a top view of the lower clamp of FIG. 17;

    FIGURE 21 is a cross-sectional view of the lower clamp taken along line 21-21 of FIG. 20;

    FIGURE 22 is a side view of a double-ended clamp screw of the tool holder of FIG. 1 according to an embodiment of the invention;

    FIGURE 23 is a perspective of a lower clamp according to an alternate embodiment of the invention;

    FIGURE 24 is a top view of the lower clamp of FIG. 23;

    FIGURE 25 is a cross-sectional view of a tool holder with a ball clamping mechanism in the locked position according to an alternate embodiment of the invention; and

    FIGURE 26 is a cross-sectional view of the tool holder with the ball clamping mechanism of FIG. 25 in the unlocked position.


    DETAILED DESCRIPTION OF EMBODIMENTS



    [0009] Referring now to FIGS. 1-4, a tool holder is shown generally at 10 according to an embodiment of the invention. The tool holder 10 includes a generally cylindrical, annular body 12, a cutting head 14, a retention knob 16, radial stops 18, and a ball clamping mechanism, shown generally at 20. The ball clamping mechanism 20 includes an upper clamp 22, a lower clamp 24 and a double-ended clamp screw 26. In FIGS. 1 and 2, the tool holder 10 is shown in the locked position, and in FIGS. 3 and 4, the tool holder 10 is shown in the unlocked position.

    [0010] Referring now to FIGS. 5-7, the body 12 is annular and generally cylindrical in shape and includes a cavity 28 for coolant at one end that is centrally located with respect to a longitudinal axis 30 of the body 12. The other end of the body 12 includes a cutting head receiving receptacle 32 with a slightly larger diameter than the cavity 28 for receiving the cutting head 14 and retention knob 16. hi one embodiment, one end of the receptacle 32 has an included taper angle of about 5 degrees, 44 minutes (1 : 10). The end of the receptacle 32 is in communication with a generally elliptical, radially-extending ball clamping mechanism aperture 34. A ball clamping mechanism aperture 34 is substantially perpendicular and is substantially mirror symmetric with respect to the longitudinal axis 30 of the body 12. The other end 32b of the cutting head receiving receptacle 32 interacts with the cutting head 14 to provide an anti-rotation feature of the tool holder 10. One end of the body 12 proximate the cutting head 14 includes a flange contact surface 33 that contacts the cutting head 14 when the tool holder 10 is placed in the locked position.

    [0011] The body 12 also includes a radially-extending screw aperture 36 that is substantially perpendicular to the longitudinal axis 30 of the body 12 (and substantially parallel with the ball clamping mechanism aperture 34). In one embodiment, the radial stops 18 comprise flat head screws that are threaded into a middle portion 36a of the screw aperture 36. Ends 36b of the screw aperture 36 are tapered to provide a seating surface for the flat head screws 18. It will be appreciated that the invention is not limited by the use of flat head screws as the radial stops 18, and that the invention can be practiced by using other similar means, such as pins, and the like. The screw aperture 36 is substantially mirror symmetric with respect to the longitudinal axis 30 of the body 12. In one embodiment, each end 36b is cone-shaped with an included angle of about ninety (90) degrees. A portion 36c of each end 36b is in communication with the ball clamping mechanism aperture 34. In this manner, a portion of the flat head screws 18 are able to engage the upper and lower clamps 22, 24 and limit radial movement of the upper and lower clamps 22, 24. The ball clamping mechanism 20 can be removed from the ball clamping mechanism aperture 34 of the body 12 by removing one or both flat head screws 18.

    [0012] Referring now to FIGS. 8-10, the cutting head 14 is shown according to an embodiment of the invention. One end of the cutting head 14 includes a cutting end portion 38 that is generally cylindrical in shape and may have a central cavity 40 for receiving a cutting tool (not shown), if necessary. The cutting head 14 also includes a tapered end portion 42 at an opposite end and having an outer surface that is tapered in a similar fashion as the cutting head receiving receptacle 32 of the body 12. In an embodiment, the tapered end portion 42 has an included taper angle of about 5 degrees, 44 minutes (1 :10). The tapered end portion 42 is generally annular having a threaded aperture 44 in communication with the central cavity 40. The threaded aperture 44 is capable of receiving the retention knob 16. However, it will be appreciated that the retention knob 16 can be integrally formed with the cutting head 14, as shown in FIGS. 25 and 26. In addition, in some embodiments, the central cavity 40 may be omitted. In the illustrated embodiment, the threaded aperture 44 and the central cavity 40 are substantially aligned with a central, longitudinal axis 46 of the cutting head 14.

    [0013] The cutting head 14 includes a middle portion 48 with an anti-rotation feature 48a and a face contact surface 48b that contacts the flange contact surface 33 of the body 12 when the tool holder 10 is in the locked position. In the illustrated embodiment, the anti-rotation feature comprises two flats 48a that interact with a wall 32a of the cutting head receiving receptacle 32 of the body 12 to prevent rotation of the cutting head 14 with respect to the body 12. In the illustrated embodiment, the middle portion 48 has a pair of opposing flats 48a. However, the invention can be practiced with any desirable number of flats 48a that prevent rotation of the cutting head 14.

    [0014] Referring now to FIG. 11, the retention knob 16 is shown according to an embodiment of the invention. The retention knob 16 includes a threaded end portion 50 that is capable of being threadingly received in the threaded aperture 44 at the tapered end portion 42 of the cutting head 14. hi an alternate embodiment, the retention knob 16 is integrally- formed with the tapered end portion 42 of the cutting head 14. The opposite end of the retention knob 16 includes a generally spherical end portion 52 having a radius 57. The end portion 52 may also include a tool access 52a that is capable of receiving a tool (not shown) for assisting in threading the retention knob 16 into the cutting head 14. In the illustrated embodiment, the tool access 52a is hexagonal in shape. However, the invention can be practiced with other desirable tool access shapes that are known in the art. The end portion 52 includes an upper spherical clamp surface 51, a lower spherical clamp surface 53, and a lower spherical release surface 55. The clamp surfaces 51, 53 are located in the forward hemisphere with respect to a central axis 17 of the end portion 52. The lower spherical release surface 55 is located in the rearward hemisphere with respect to a central axis 17 of the end portion 52. The outer surface of the end portion 52 also includes a clearance diameter 52b that allows the retention knob 16 to be easily removed from the ball clamping mechanism 20 when the tool holder 10 is in the unlocked position.

    [0015] The retention knob 16 also includes a middle portion 54 having an abutment face 54a that abuts an end face 42a of the cutting head 14 when the retention knob 16 is threadingly received in the threaded aperture 44 of the cutting head 14. It should be noted that a central, longitudinal axis 56 of the retention knob 16 is substantially aligned with the central, longitudinal axis 46 of the cutting head 14 when the retention knob 16 is attached to or integrally- formed with the cutting head 14.

    [0016] The upper clamp 22 of the ball clamping mechanism 20 is shown in FIGS. 12-16. The upper clamp 22 includes a curved top surface 56 and a substantially planar bottom surface 58. As seen in FIG. 13, the top surface 56 is generally elliptical in shape similar to the aperture 34 of the body 12 to be snugly fit therein. A threaded aperture 60 extends from the top surface 56 to a passage 62 that extends to the bottom surface 58. The threaded aperture 60 is capable of threadingly receiving one end of the double-ended clamp screw 26. The upper clamp 22 includes a curved side surface 64 extending between the top surface 56 and the bottom surface 58. A dish-shaped seating surface 66 is formed at the intersection between the lop surface 56 and the side surface 64 that engages the flat head screw 18 to prevent further radial movement of the upper clamp 22 when placing the tool holder 10 in the unlocked position. As seen in FIGS, 12 and 16, a portion of the upper clamp 22 includes a generally L-shaped cutout section 68 defined by an upper wall 70 and a side wall 72 that is generally perpendicular to the upper wall 70. The L-shaped cutout section 68 is capable of receiving a portion of the lower clamp 24. A generally cylindrical upper clamp release surface 75 is formed in the side wall 72 that engages the spherical release surface 55 of the retention knob 16 when placing the tool holder 10 in the unlocked position. A cavity 74 is formed in the cutout section 68 that is capable of receiving the end portion 52 of the retention knob 16. Specifically, the cavity 74 includes a generally spherical upper clamp cavity portion 74a and a generally cylindrical upper clamp cavity portion 74b. The generally spherical upper clamp cavity portion 74a is formed having a radius 77 that is slightly larger than the radius 57 of the generally spherical end portion 52 of the retention knob 16. For example, the radius 77 may be up to about 0.010 inches larger than the radius 57 of the end portion 52 of the retention knob 16. A portion of the wall of the generally cylindrical upper clamp cavity portion 74b defines a generally cylindrical upper clamp surface 76 that engages the upper spherical clamp surface 51 of the retention knob 16 when the tool holder 10 is placed in the locked position.

    [0017] The lower clamp 24 of the ball clamping mechanism 20 is shown in FIGS. 17-21. The lower clamp 24 includes a curved bottom surface 78 and a substantially planar top surface 80. As seen in FIG. 18, the bottom surface 78 is generally elliptical in shape similar to the aperture 34 of the body 12 to be snugly fit therein. A threaded aperture 82 extends from the bottom surface 78 to the top surface 80. The threaded aperture 82 is capable of threadingly receiving one end of the double-ended clamp screw 26. The lower clamp 24 includes a curved side surface 84 extending between the bottom surface 78 and the top surface 80. A dish-shaped seating surface 86 is formed at the intersection between the bottom surface 78 and the side surface 84 that engages the flat head screw 18 to prevent further radial movement of the lower clamp 24 when placing the tool holder 10 in the unlocked position. As seen in FIGS. 17 and 21, a portion of the lower clamp 24 includes a generally L-shaped cutout section 88 defined by an upper wall 90 and a side wall 92 that is generally perpendicular to the upper wall 90. The L-shaped cutout section 88 is capable of receiving a portion of the upper clamp 22. A cavity 94 is formed in the cutout section 88 that is capable of receiving the generally spherical end portion 52 of the retention knob 16. Specifically, the cavity 94 includes a generally spherical lower clamp cavity portion 94a and a generally cylindrical lower clamp cavity portion 94b. Similar to the upper clamp 22, the generally spherical lower clamp cavity portion 94a of the lower clamp 24 is formed having a radius 91 that is slightly larger than the radius 57 of the end portion 52 of the retention knob 16. For example, the radius 97 may be up to about 0.010 inches larger than the radius 57 of the end portion 52 of the retention knob 16. A portion of the wall of the generally cylindrical lower clamp cavity portion 94b defines a generally cylindrical lower clamp surface 96 that engages the lower spherical clamp surface 55 of the retention knob 16 when the tool holder 10 is placed in the locked position.

    [0018] Referring now to FIG. 22, the double-ended clamp screw 26 is shown according to an embodiment of the invention. The clamp screw 26 is generally cylindrical in shape and includes a first end portion 98, a second end portion 100 and a middle portion 102 between the first and second end portions 98 , 100. The outer surface of the first end portion 98 is threaded, for example, with right hand threads, while the outer surface of the second end portion 100 is threaded, for example, with left hand threads. The first and second end portions 98, 100 are capable of being threaded into the threaded apertures 60, 82 of the upper and lower clamps 22, 24, respectively. In the illustrated embodiment, the first end portion 98 has a slightly smaller diameter than the second end portion 100, and the middle portion 102 has a smaller diameter than both the first and second end portions 98, 100. However, the invention can be practiced with the first and second end portions 98, 100 having approximately the same diameter. One of the end portions, for example, the second end portion 100 includes a tool access 104 for allowing a tool to be inserted therein. In the illustrated embodiment, the tool access 104 is hexagonal in shape.

    [0019] To assemble the tool holder 10, the retention knob 16 is threaded onto the cutting head 14, The retention knob 16 can be threaded onto the cutting head 14 at any time during the assembly process. In an alternate embodiment, the retention knob 16 is integrally- formed with the cutting head 14. In this embodiment, the retention knob 16 does not need to be threaded onto the cutting head 14. The clamping assembly 20 is assembled by threading the double-ended clamp screw 26 into the threaded apertures 60, 82 of the upper and lower clamps 22, 24, respectively. Then, the clamping assembly 20 is inserted into the aperture 34 of the body. The flat head screws 18 are then threaded into the screw apertures 36 to limit radial movement of the clamping mechanism 20 and to secure the clamping mechanism 20 in the body 12.

    [0020] In operation, the double-ended clamp screw 26 can be rotated in a counterclockwise direction to move the tool holder 10 from the locked position to the unlocked position. During rotation of the clamp screw 26, the generally cylindrical release surface 75 formed in the side wall 72 of the upper clamp 22 engages the spherical release surface 55 of the retention knob 16 to cause the lower clamp 24 to contact the radial stop 18. Further rotation causes the cylindrical release surface 75 of the upper clamp 22 to act on the spherical release surface 55 of the retention knob 16 to cause the cutting head 14 to be released from the tool holder body 12. At this point, the tool holder 10 is in the unlocked position. To place the tool holder 10 in the locked position, the double-ended clamp screw 26 can be rotated in a clockwise direction to cause the upper and lower clamps 22, 24 to move toward each other until the generally cylindrical upper and lower clamp surfaces 76, 96 of the upper and lower clamps, 22, 24 engage the upper and lower spherical clamp surfaces 51, 55 of the end portion 52 of the retention knob 16. The generally cylindrical upper and lower clamp surfaces 76, 96 elastically deform during the engagement with the generally spherical clamp surfaces 51, 55 of the retention knob 16 to form a lenticular contact area and securely hold the cutting head 14 in face contact with the body 12.

    [0021] It is noted that the cutting head 14 and the retention knob 16 are drawn into the body 12 slightly in the direction of the longitudinal axis 30 of the body 12 when the tool holder 10 is placed in the locked position, as indicated by the double-arrow shown in FIGS. 1 and 3. This may cause the upper and lower clamps 22, 24 to become slightly non-parallel with respect to each other (and to the longitudinal axis 30 of the body 12), and the double- ended clamp screw 26 to become seized when the tool holder 10 is placed in the unlocked position.

    [0022] As shown in FIG. 2, a gap 106 exists between the upper and lower clamps 22, 24 when the tool holder 10 is placed in the locked position. To help overcome the potential seizure of the double-ended clamp screw 26, a lower clamp 24' is shown in FIGS. 23 and 24 according to an alternative embodiment. The lower clamp 24' is substantially identical to the lower clamp 24, except that the lower clamp 24' includes a step 108 opposite the screw seating surface 86. The step 108 substantially fills the gap 106 such that a top surface 108a of the step 108 contacts the lower surface of the upper clamp 22 to help maintain the upper and lower clamps 22, 24' to be substantially parallel to each other (and to the longitudinal axis 30 of the body 12) when the tool holder 10 is placed in the locked position.

    [0023] Another embodiment to maintain the upper and lower clamps in a substantially parallel orientation incorporates an extension of the rear portions of the upper and lower clamps in an axial direction. This extension or tab cooperates with a ledge on each side of the body to provide a radial stop for the rear of the clamp. This embodiment replaces the step 108 of the previous embodiment. The location of the radial stop is designed to keep the clamps substantially parallel when the clamps are in the locked position.

    [0024] In the earlier embodiments, the retention knob 16 is located forward of the double-ended clamp screw 26 of the clamping mechanism 20, as shown in FIGS. 1-4. However, it is noted that the clamp surfaces 51, 53 are located in the forward hemisphere with respect to the central axis 17 of the end portion 52 of the retention knob 16. Therefore, it may be advantageous to position the double-ended clamp screw 26 more forward with respect to the retention knob 16 and the upper and lower clamp surfaces 76, 96 to cause the clamping force of the upper and lower clamps 22, 24 onto the retention knob 16 to be more radial and less axial.

    [0025] Referring now to FIGS. 25 and 26, a tool holder 10' is shown according to an alternative embodiment of the invention. For brevity, the reference numbers of similar elements of the tool holder 10 are increased by 100 in the tool holder 10' and will not be explained in detail.

    [0026] The tool holder 10' includes a generally cylindrical, annular body 112, a cutting head 114, a retention knob 116, a pair of flat head screws 118, and a ball clamping mechanism, shown generally at 120. The ball clamping mechanism 120 includes an upper clamp 122, a lower clamp 124 and a double-ended clamp screw 126. In FIG. 25, the tool holder 10' is shown in the locked position, and in FIG. 26, the tool holder 10' is shown in the unlocked position.

    [0027] In this embodiment, a middle portion 202 of the double-ended clamp screw 126 is disposed within a slot 117 in the end portion 152 of the retention knob 116 in the embodiment of the tool holder 10' shown in FIGS. 25 and 26. By this arrangement, the double-ended clamp screw 126 is positioned more forward with respect to the clamp surfaces 51, 52. In addition, the middle portion 202 of the clamp screw 126 acts as an anti-rotation feature of the tool holder 10 and prevents rotation of the cutting head 114 with respect to the body 112. Thus, the flats 48b on the cutting head 14 of the embodiment shown in FIGS. 1-22 are not needed in the embodiment shown in FIGS. 25 and 26. In this embodiment, it is also noted that the cutting head 114 is integrally-formed with the retention knob 116. However, it will be appreciated that the integrally- formed cutting head/retention knob can also be used in the earlier embodiments.

    [0028] As described above, the tool holder 10, 10' of the invention provides a tool holder with a ball clamp mechanism that is simple and cost-effective design, but holds the cutting tool securely in place with face contact between the cutting head and the body of the tool holder.


    Claims

    1. A tool holder (10; 10'), comprising:

    a body (12; 112) having a clamping mechanism aperture (34; 134) for receiving a clamping mechanism (20, 120);

    a cutting head (14; 114) having a cutting end portion (38; 138), a tapered end portion (42; 142), and a middle portion (48; 148) located between the cutting end and the tapered end portion;

    a retention knob (16; 116) located at the tapered end portion of the cutting head, the retention knob including a end portion (52; 152) at least partially disposed within the body, the end portion including an upper clamp surface (51; 151) and a lower clamp surface (53; 153); and

    the clamping mechanism comprising:

    an upper clamp (22; 122) having an upper clamp cavity (74; 174) capable of receiving the end portion of the retention knob and defining an upper clamp surface (76);

    a lower clamp (24; 124) having a lower clamp cavity (94; 194) capable of receiving the end portion of the retention knob and defining a lower clamp surface (96); and

    a double-ended clamp screw (26; 126) for threadingly receiving the upper and lower clamps, wherein rotation of the double-ended clamp screw in a first direction causes the upper and lower clamp surfaces of the upper and lower clamps to move toward each other,

    characterized in that
    the clamping mechanism is a ball clamping mechanism (20, 120),
    the end portion of the retention knob is a generally spherical end portion (52, 152), whose upper and lower clamp surfaces (51, 53) are spherical clamp surfaces,
    wherein the upper clamp cavity includes a generally spherical upper clamp cavity portion (74a; 174a) and a generally cylindrical upper clamp cavity portion (74b; 174b), a portion of the generally cylindrical upper clamp cavity portion defining the upper clamp surface (76; 176) which is a generally cylindrical clamp surface,
    wherein the lower clamp cavity includes a generally spherical lower clamp cavity portion (94a, 194a) and a generally cylindrical lower clamp cavity portion (94b, 194b), a portion of the generally cylindrical lower clamp cavity portion defining the lower clamp surface (96, 196) which is a generally cylindrical clamp surface,
    wherein rotation of the double-ended clamp screw in said first direction causes the generally cylindrical upper and lower clamp surfaces (76, 96) to engage the generally spherical upper and lower spherical clamp surfaces (51, 53) of the retention knob, respectively, and
    wherein the generally cylindrical upper and lower clamp surfaces (76, 96) elastically deform during engagement with the generally spherical upper and lower clamp surfaces of the retention knob to form a lenticular contact area and securely hold the cutting head in face contact with the body and place the tool holder in a locked position.
     
    2. The tool holder according to claim 1, wherein the upper clamp further includes a generally cylindrical release surface (75; 175), and wherein the generally spherical end portion of the retention knob further includes a generally spherical release surface (55; 155), and wherein the generally cylindrical release surface of the upper clamp engages the generally spherical release surface of the retention knob when the double-ended clamp screw is rotated in a second, opposite direction to cause the upper and lower clamps to move away from each other and place the tool holder in an unlocked position.
     
    3. The tool holder according to claim 1 or claim 2, wherein the body further comprises a pair of threaded screw apertures (36; 136) capable of receiving stops (18; 118) that limit radial movement of the upper and lower clamps.
     
    4. The tool holder according to any of the preceding claims, wherein the ball clamp mechanism aperture is substantially perpendicular to a longitudinal axis (30) of the body.
     
    5. The tool holder according to any of the preceding claims, wherein the lower clamp includes a step (108) for maintaining a substantially parallel relationship between the upper and lower clamps when the tool holder is placed in the locked position.
     
    6. The tool holder according to claim 5, wherein the step (108) has a surface (108a) that engages the upper clamp for maintaining a substantially parallel relationship between the upper and lower clamps when the tool holder is placed in the locked position.
     
    7. The tool holder according to any of the preceding claims, wherein the body includes a cutting head receiving receptacle (32; 132) for receiving the cutting head and the retention knob, and wherein the cutting head receiving receptacle has an included angle of about 5 degrees, 44 minutes.
     
    8. The tool holder according to claim 7, wherein the cutting head includes an end portion (38; 138) having an outer surface having a taper angle approximately equal to the taper angle of the cutting head receiving receptacle.
     
    9. The tool holder according to any of the preceding claims, wherein the body further includes a flange contact surface (33; 133), and wherein the cutting head further includes a face contact surface (48b; 148b) that contacts the flange contact surface of the body when the tool holder is in the locked position.
     
    10. The tool holder according to any of the preceding claims, wherein the tool holder further includes an anti-rotation feature for preventing rotation of the cutting head with respect to the body.
     
    11. The tool holder according to claim 10, wherein the anti-rotation feature comprises two or more flats (48a) on the cutting head that interact with a wall (32a) of the cutting head receiving receptacle of the body to prevent rotation of the cutting head with respect to the body.
     
    12. The tool holder according to claim 10, wherein the anti-rotation feature comprises the double-ended clamp screw having a middle portion (102) disposed within a slot (117) in the retention knob.
     
    13. The tool holder according to claim 12, wherein the generally spherical end portion includes the slot (117), the double-ended clamp screw including a middle portion (202) disposed within the slot of the retention knob.
     
    14. The tool holder according to any of the preceding claims, wherein a radius (77, 97) of the upper and lower clamp cavities of the upper and lower clamps is larger than a radius of the spherical end portion of the retention knob.
     


    Ansprüche

    1. Werkzeughalter (10; 10'), umfassend:

    einen Körper (12; 112) mit einer Klemmmechanismus-Öffnung (34; 134) für die Aufnahme eines Klemmmechanismus (20, 120);

    einen Schneidkopf (14; 114) mit einem Schneidende-Abschnitt (38; 138), einem sich verjüngenden Endabschnitt (42; 142) und einem Mittelabschnitt (48; 148), der sich zwischen dem Schneidende und dem sich verjüngendem Endabschnitt befindet;

    einen Rückhalteknauf (16; 116), der sich an dem sich verjüngendem Endabschnitt des Schneidkopfes befindet, wobei der Rückhalteknauf einen Endabschnitt (52; 152) beinhaltet, der zumindest teilweise innerhalb des Körpers angeordnet ist, wobei der Endabschnitt eine obere Klemmfläche (51; 151) und eine untere Klemmfläche (53; 153) beinhaltet; und

    wobei der Klemmmechanismus umfasst:

    eine obere Klammer (22; 122) mit einem oberen Klammerhohlraum (74; 174), der geeignet ist zur Aufnahme des Endabschnitts des Rückhalteknaufs und der eine obere Klammerfläche (76) bestimmt;

    eine untere Klammer (24; 124) mit einem unteren Klammerhohlraum (94; 194), der geeignet ist zur Aufnahme des Endabschnitts des Rückhalteknaufs und der eine untere Klammerfläche (96) bestimmt

    eine doppelseitige Klammerschraube (26; 126) zur Gewindeaufnahme der oberen und unteren Klammern, wobei Drehung der doppelseitigen Klammerschraube in einer ersten Richtung bewirkt, dass die oberen und unteren Klammerflächen der oberen und unteren Klammern sich aufeinander zu bewegen,

    dadurch gekennzeichnet, dass
    der Klemmmechanismus ein Kugelklemmmechanismus (20, 120) ist,
    der Endabschnitt des Rückhalteknaufs ein im Allgemeinen kugelförmiger Endabschnitt (52, 152) ist, dessen obere und untere Klammerflächen (51, 53) sphärisch Klammerflächen sind,
    wobei der obere Klammerhohlraum einen im Allgemeinen kugelförmigen oberen Klammerhohlraum-Abschnitt (74a; 174a) und einen im Allgemeinen zylindrischen oberen Klammerhohlraum-Abschnitt (74b; 174b) beinhaltet, wobei ein Abschnitt des im Allgemeinen zylindrischen oberen Klammerhohlraum-Abschnitt eine obere Klammerfläche (76; 176) bestimmt, die eine im Allgemeinen zylindrische Klammerfläche ist,
    wobei der untere Klammerhohlraum einen im Allgemeinen kugelförmigen unteren Klammerhohlraum-Abschnitt (94a; 194a) und einen im Allgemeinen zylindrischen unteren Klammerhohlraum-Abschnitt (94b; 194b) beinhaltet, wobei ein Abschnitt des im Allgemeinen zylindrischen unteren Klammerhohlraum-Abschnitt eine untere Klammerfläche (96; 196) bestimmt, die eine im Allgemeinen zylindrische Klammerfläche ist,
    wobei eine Drehung der doppelseitigen Klammerschraube in die besagte erste Richtung verursacht, dass die im Allgemeinen zylindrischen oberen und unteren Klammerflächen (76, 96) in die im Allgemeinen kugelförmige oberen bzw. unteren sphärischen Klammerflächen (51, 53) des Rückhalteknaufs eingreifen, und
    wobei die im Allgemeinen zylindrischen oberen und unteren Klammerflächen (76, 96) bei Eingriff mit den im Allgemeinen kugelförmigen oberen und unteren Klammerflächen des Rückhalteknaufs sich elastisch verformen, um einen lentikularen Kontaktbereich zu bilden und den Schneidkopf sicher in direktem Kontakt mit dem Körper halten und den Werkzeughalter in eine verriegelte Position bringen.
     
    2. Werkzeughalter nach Anspruch 1, wobei die obere Klammer ferner eine im Allgemeinen zylindrische Trennfläche (75; 175) beinhaltet und wobei der im Allgemeinen kugelförmige Endabschnitt des Rückhalteknaufs ferner eine im Allgemeinen kugelförmige Trennfläche (55; 155) beinhaltet und wobei die Allgemeinen zylindrische Trennfläche der oberen Klammer in die im Allgemeinen kugelförmige Trennfläche des Rückhalteknaufs eingreift, wenn die doppelseitige Klammerschraube in einer zweiten, entgegengesetzten Richtung gedreht wird, und damit verursacht, dass sich die oberen und unteren Klammern voneinander fort bewegen und den Werkzeughalter in eine entriegelten Position bringen.
     
    3. Werkzeughalter nach Anspruch 1 oder Anspruch 2, wobei der Körper ferner ein Paar von Gewindeschraubenöffnungen (36; 136) umfasst, die geeignet sind zur Aufnahme von Anschlägen (18; 118), welche die radiale Bewegung der oberen und unteren Klammern begrenzen.
     
    4. Werkzeughalter nach einem der vorstehenden Ansprüche, wobei die Kugelklemmmechanismus-Öffnung im Wesentlichen senkrecht zu einer Längsachse (30) des Körpers steht.
     
    5. Werkzeughalter nach einem der vorstehenden Ansprüche, wobei die untere Klammer eine Stufe (108) beinhaltet, um eine im Wesentlichen parallele Beziehung zwischen den oberen und unteren Klammern beizubehalten, wenn der Werkzeughalter in die verriegelte Position gebracht wird.
     
    6. Werkzeughalter nach Anspruch 5, wobei die Stufe (108) eine Oberfläche (108a) aufweist, die in die obere Klammer eingreift, um eine im Wesentlichen parallele Beziehung zwischen den oberen und unteren Klammern beizubehalten, wenn der Werkzeughalter in die verriegelte Position gebracht wird.
     
    7. Werkzeughalter nach einem der vorstehenden Ansprüche, wobei der Körper eine einen Schneidkopf aufnehmende Aufnahme (32; 132) zum Aufnehmen des Schneidkopfes und des Rückhalteknaufs beinhaltet und wobei die den Schneidkopf aufnehmende Aufnahme einen eingeschlossenen Winkel von etwa 5 Grad, 44 Minuten aufweist.
     
    8. Werkzeughalter nach Anspruch 7, wobei der Schneidkopf einen Endabschnitt (38; 138) umfasst, der eine Außenfläche mit einem Konuswinkel aufweist, der in etwa gleich des Konuswinkels des Schneidkopfes ist.
     
    9. Werkzeughalter nach einem der vorstehenden Ansprüche, wobei der Körper ferner eine Flansch-Kontaktfläche (33; 133) beinhaltet und wobei der Schneidkopf ferner eine Vorderseiten-Kontaktfläche (48b; 148b) beinhaltet, die mit der Flansch-Kontaktfläche des Körper in Kontakt steht, wenn der Werkzeughalter in die verriegelte Position gebracht wird.
     
    10. Werkzeughalter nach einem der vorstehenden Ansprüche, wobei der Werkzeughalter ferner eine Verdrehsicherung beinhaltet, um eine Drehung des Schneidkopfes relativ zu dem Körper zu verhindern.
     
    11. Werkzeughalter nach Anspruch 10, wobei die Verdrehsicherung zwei oder mehr Flachflächen (48a) auf dem Schneidkopf umfasst, die mit einer Wand (32a) der den Schneidkopf aufnehmenden Aufnahme des Körpers zusammenwirken, um eine Drehung des Schneidkopfes relativ zu dem Körper zu verhindern.
     
    12. Werkzeughalter nach Anspruch 10, wobei die Verdrehsicherung die doppelseitige Klammerschraube mit einem Mittelabschnitt (102) umfasst, der in einem Schlitz (117) in dem Rückhalteknauf angeordnet ist.
     
    13. Werkzeughalter nach Anspruch 12, wobei der im Allgemeinen kugelförmige Endabschnitt den Schlitz (117) beinhaltet, wobei die doppelseitige Klammerschraube einen Mittelabschnitt (202) beinhaltet, der in einem Schlitz in dem Rückhalteknauf angeordnet ist.
     
    14. Werkzeughalter nach einem der vorstehenden Ansprüche, wobei ein Radius (77, 97) der oberen und unteren Klammerhohlräume der oberen und unteren Klammern größer ist als ein Radius des sphärischen Endabschnitts des Rückhalteknaufs.
     


    Revendications

    1. Porte-outil (10 ; 10'), comprenant :

    un corps (12 ; 112) comportant une ouverture pour mécanisme de serrage (34 ; 134) destinée à recevoir un mécanisme de serrage (20, 120) ;

    une tête de coupe (14 ; 114) comportant une partie d'extrémité de coupe (38 ; 138), une partie d'extrémité conique (42 ; 142) et une partie milieu (48 ; 148) située entre la partie d'extrémité de coupe et la partie d'extrémité conique ;

    un bouton de retenue (16; 116) situé au niveau de la partie d'extrémité conique de la tête de coupe, le bouton de retenue incluant une partie d'extrémité (52; 152) au moins partiellement disposée à l'intérieur du corps, la partie d'extrémité incluant une surface de serrage supérieure (51 ; 151) et une surface de serrage inférieure (53 ; 153) ; et

    le mécanisme de serrage comprenant :

    une mâchoire supérieure (22 ; 122) comportant une cavité de serrage supérieure (74 ; 174) pouvant recevoir la partie d'extrémité du bouton de retenue et définissant une surface de serrage supérieure (76) ;

    une mâchoire inférieure (24 ; 124) comportant une cavité de serrage inférieure (94 ; 194) pouvant recevoir la partie d'extrémité du bouton de retenue et définissant une surface de serrage inférieure (96) ; et

    une vis de serrage à double extrémité (26; 126) destinée à recevoir par vissage les mâchoires supérieure et inférieure, dans lequel la rotation de la vis de serrage à double extrémité dans un premier sens amène les surfaces de serrage supérieure et inférieure des mâchoires supérieure et inférieure à se déplacer l'une vers l'autre,

    caractérisé en ce que
    le mécanisme de serrage est un mécanisme de serrage à bille (20, 120),
    la partie d'extrémité du bouton de retenue est une partie d'extrémité de forme générale sphérique (52, 152) dont les surfaces de serrage supérieure et inférieure (51, 53) sont des surfaces de serrage sphériques,
    dans lequel la cavité de serrage supérieure inclut une partie cavité de serrage supérieure de forme générale sphérique (74a ; 174a) et une partie cavité de serrage supérieure de forme générale cylindrique (74b ; 174b), une partie de la partie cavité de serrage supérieure de forme générale cylindrique définissant la surface de serrage supérieure (76 ; 176) qui est une surface de serrage de forme générale cylindrique,
    dans lequel la cavité de serrage inférieure inclut une partie cavité de serrage inférieure de forme générale sphérique (94a, 194a) et une partie cavité de serrage inférieure de forme générale cylindrique (94b, 194b), une partie de la partie cavité de serrage inférieure de forme générale cylindrique définissant la surface de serrage inférieure (96, 196) qui est une surface de serrage de forme générale cylindrique,
    dans lequel la rotation de la vis de serrage à double extrémité dans ledit premier sens amène les surfaces de serrage supérieure et inférieure de forme générale cylindrique (76, 96) à venir en prise respectivement avec les surfaces de serrage sphériques supérieure et inférieure de forme générale sphérique (51, 53) du bouton de retenue, et
    dans lequel les surfaces de serrage supérieure et inférieure de forme générale cylindrique (76, 96) se déforment élastiquement lors de la mise en prise avec les surfaces de serrage supérieure et inférieure de forme générale sphérique du bouton de retenue pour former une zone de contact lenticulaire et tenir solidement la tête de coupe en contact direct avec le corps et placer le porte-outil dans une position verrouillée.
     
    2. Porte-outil selon la revendication 1, dans lequel la mâchoire supérieure comprend en outre une surface de libération de forme générale cylindrique (75 ; 175), et dans lequel la partie d'extrémité de forme générale sphérique du bouton de retenue inclut en outre une surface de libération de forme générale sphérique (55 ; 155), et dans lequel la surface de libération de forme générale sphérique de la mâchoire supérieure vient en prise avec la surface de libération de forme générale sphérique du bouton de retenue lorsque la vis de serrage à double extrémité est mise en rotation dans un deuxième sens opposé pour amener les mâchoires supérieure et inférieure à s'écarter l'une de l'autre et placer le porte-outil dans une position déverrouillée.
     
    3. Porte-outil selon la revendication 1 ou la revendication 2, dans lequel le corps comprend en outre une paire d'orifices de vis filetés (36 ; 136) pouvant recevoir des butées (18 ; 118) qui limitent le déplacement radial des mâchoires supérieure et inférieure.
     
    4. Porte-outil selon l'une quelconque des revendications précédentes, dans lequel l'ouverture du mécanisme de serrage à bille est sensiblement perpendiculaire à un axe longitudinal (30) du corps.
     
    5. Porte-outil selon l'une quelconque des revendications précédentes, dans lequel la mâchoire inférieure inclut un redent (108) destiné à maintenir une relation sensiblement parallèle entre les mâchoires supérieure et inférieure lorsque le porte-outil est placé dans la position verrouillée.
     
    6. Porte-outil selon la revendication 5, dans lequel le redent (108) comporte une surface (108a) qui vient en prise avec la mâchoire supérieure pour maintenir une relation sensiblement parallèle entre les mâchoires supérieure et inférieure lorsque le porte-outil est placé dans la position verrouillée.
     
    7. Porte-outil selon l'une quelconque des revendications précédentes, dans lequel le corps inclut un logement de réception de tête de coupe (32 ; 132) destiné à recevoir la tête de coupe et le bouton de retenue, et dans lequel le logement de réception de tête de coupe présente un angle au sommet d'environ 5 degrés, 44 minutes.
     
    8. Porte-outil selon la revendication 7, dans lequel la tête de coupe inclut une partie d'extrémité (38 ; 138) comportant une surface extérieure ayant un angle de cône approximativement égal à l'angle de cône du logement de réception de la tête de coupe.
     
    9. Porte-outil selon l'une quelconque des revendications précédentes, dans lequel le corps inclut en outre une surface de contact de bride (33 ; 133), et dans lequel la tête de coupe inclut en outre une surface de contact de face (48b ; 148b) qui vient en contact avec la surface de contact de bride du corps lorsque le porte-outil est dans la position verrouillée.
     
    10. Porte-outil selon l'une quelconque des revendications précédentes, dans lequel le porte-outil inclut en outre un système anti-rotation pour empêcher la rotation de la tête de coupe par rapport au corps.
     
    11. Porte-outil selon la revendication 10, dans lequel le système anti-rotation comprend au moins deux méplats (48a) sur la tête de coupe qui interagissent avec une paroi (32a) du logement de réception de la tête de coupe du corps pour empêcher la rotation de la tête de coupe par rapport au corps.
     
    12. Porte-outil selon la revendication 10, dans lequel le système anti-rotation comprend la vis de serrage à double extrémité comportant une partie milieu (102) disposée à l'intérieur d'une fente (117) dans le bouton de retenue.
     
    13. Porte-outil selon la revendication 12, dans lequel la partie d'extrémité de forme générale sphérique inclut la fente (117), la vis de serrage à double extrémité incluant une partie milieu (202) disposée à l'intérieur de la fente du bouton de retenue.
     
    14. Porte-outil selon l'une quelconque des revendications précédentes, dans lequel un rayon (77, 97) des cavités de serrage supérieure et inférieure des mâchoires supérieure et inférieure est supérieur à un rayon de la partie d'extrémité sphérique du bouton de retenue.
     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



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    Patent documents cited in the description