Tool holder and a parting and grooving tool for an indexable turret, and a machining method therefor

Abstract

A tool holder and a parting and grooving tool for an indexable turret have a plurality of tool stations, The adjacent tool stations have a predetermined angular spacing. The tool holder includes a mounting portion and a projected portion, which are connected. The mounting portion has a flat surface extending in an interface plane and the projected portion has a recess for holding the parting and grooving tool. The parting and grooving tool includes a cutting portion and a clamping portion. The cutting portion includes a cutting edge and the clamping portion includes a rear end surface. The parting and grooving tool is mountable in the recess such that a distance from the interface plane to the rear end surface of the parting and grooving tool is greater than a distance from the interface plane to the cutting portion of the parting and grooving tool.

Claims

1. A tool holder and a parting and grooving tool arranged for being mounted on an indexable turret having a plurality of tool stations, wherein adjacent tool stations having a predetermined angular spacing, and wherein the turret is movable in a direction towards the tool station, which is along the X axis direction, the tool holder comprising a mounting portion, and a projected portion, wherein the mounting portion includes a flat surface defining an interface plane, wherein the projected portion includes a recess for holding the parting and grooving tool, wherein the projected portion and the mounting portion are connected to each other; and the parting and grooving tool comprising a parting and grooving blade, the blade including a cutting portion, and a clamping portion, wherein the cutting portion includes a parting and grooving insert having a cutting edge and a rake face, wherein the clamping portion includes a top and a rear end surface, wherein the parting and grooving tool is mountable in the recess such that a distance from the interface plane to the rear end surface of the parting and grooving tool is greater than a distance from the interface plane to the cutting portion of the parting and grooving tool, wherein the parting and grooving tool is elongated along a grooving tool axis, which is in a cutting direction along the Y axis direction, and wherein the top surface of the blade and the rake face are facing in a same or substantially same direction.

2. The tool holder and parting and grooving tool according to claim 1, wherein the parting and grooving tool axis is inclined by an angle in relation to the interface plane, wherein said angle is at least 1 and not more than 45.

3. The tool holder and parting and grooving tool according to claim 1, wherein the mounting portion includes a hole pattern.

4. The tool holder and parting and grooving tool according to claim 1, wherein the parting and grooving tool an insert seat for receiving the parting and grooving insert, wherein the parting and grooving blade includes opposite first and second surfaces, and opposite third and fourth surfaces, wherein a blade width is defined as a shortest distance between the first and second surfaces, wherein the cutting edge defines an insert width, and wherein the insert width is greater than the blade width.

5. The tool holder and parting and grooving tool according to claim 4, wherein the recess includes a rear end surface and an opposite opening, a first side surface, a second side surface and a bottom surface, wherein a portion of the third surface of the parting and grooving tool is in contact with a portion of the second side surface of the recess, and wherein a portion of the fourth surface is in contact with a portion of the first side surface of the recess.

6. The tool holder and parting and grooving tool according to claim 1, wherein the tool holder includes positioning means, wherein said positioning means include a stop surface arranged for being in contact with the rear surface of the parting and grooving tool, and wherein the stop surface is moveable along or parallel to a parting and grooving tool axis.

7. The tool holder and parting and grooving tool according to claim 1, wherein the recess is offset in relation to the flat surface of the mounting portion.

8. A tool post for a lathe, the tool post comprising: a tool holder and a parting and grooving tool according to claim 1; and a turret, wherein the turret is rotatable around a turret axis, wherein the turret includes a plurality of tool stations, wherein adjacent tool stations are spaced apart by a predetermined angle, wherein the mounting portion of the tool holder is detachably connected to a tool station of the turret, and wherein the cutting edge intersects a plane including an adjacent tool station and the turret axis.

9. The tool post according to claim 8, wherein the predetermined angle separating adjacent tool stations is equal to or substantially equal to an angle, and wherein a parting and grooving tool axis is inclined by said angle in relation to the interface plane.

10. The tool post according to claim 8, wherein the cutting edge intersects or substantially intersects a plane including a center point of the adjacent tool station and the turret axis.

11. The tool post according to claim 8, wherein the turret includes a front surface, an opposite rear surface and a peripheral surface connecting the front and rear surfaces, wherein the peripheral surface includes the tool stations.

12. The tool post according to claim 11, wherein the projected portion is outside a volume limited by a plane having the front surface and a plane having the rear surface.

13. The tool post according to claim 8, wherein the turret includes a front surface, an opposite rear surface and a peripheral surface connecting the front and rear surfaces, and wherein the cutting edge is outside a volume limited by a plane having the front surface and a plane having the rear surface.

14. The tool post according to claim 8, further comprising coolant delivery means, wherein said coolant delivery means is connected to a coolant outlet associated with the adjacent tool station, and wherein said coolant delivery means is connected to the tool holder or the parting and grooving tool.

15. A method for cutting a groove in a metal work piece, comprising the steps of: providing a tool post according to claim 8, wherein the tool holder is connected to one tool station; rotating the metal work piece around a rotational axis thereof; setting the turret axis parallel to the rotational axis of the metal work piece; setting the cutting edge between the turret axis and the rotational axis of the metal work piece; and moving the tool post including the turret axis along a straight line in a feed direction towards the rotational axis of the metal work piece such that the cutting edge is moved towards the rotational axis of the metal work piece and such that a groove is formed in the metal work piece, wherein the turret is movable in a direction towards the tool station, which is along the X axis, the turret axis being the Z axis.

16. The method according to claim 15, wherein the cutting edge intersects or substantially intersects the plane including the turret axis and the rotational axis of the metal work piece.

Description

DESCRIPTION OF THE DRAWINGS

(1) The present invention will now be explained in more detail by a description of embodiments of the invention and by reference to the accompanying drawings.

(2) FIG. 1 is a side view of a turret and a tool holder and a parting and grooving tool according to a first embodiment

(3) FIG. 2 is a perspective view of the turret and a tool holder and a parting and grooving tool in FIG. 1

(4) FIG. 3 is a further perspective view of the turret and a tool holder and a parting and grooving tool in FIG. 1

(5) FIG. 4 is a side view of a turret and a tool holder and a parting and grooving tool according to a second embodiment and metal work piece

(6) FIG. 5 is a perspective view of the turret and the tool holder and the parting and grooving tool in FIG. 4

(7) FIG. 6 is a further perspective view of the turret and the tool holder and the parting and grooving tool in FIG. 4

(8) FIG. 7 is a side view of the tool holder and the parting and grooving tool according in FIG. 4

(9) FIG. 8 is a perspective view of the tool holder and the parting and grooving tool in FIG. 7

(10) FIG. 9 is a further perspective view of the tool holder and the parting and grooving tool in FIG. 7

(11) FIG. 10 is a side view of the tool holder in FIG. 7

(12) FIG. 11 is a perspective view of the tool holder in FIG. 7

(13) FIG. 12 is a further perspective view of the tool holder in FIG. 7

(14) FIG. 13 is a top view of a tool station

(15) FIG. 14 is a rear view of a mounting portion of a tool holder

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

(16) Reference is made to FIGS. 1-3 which show tool post 3 for a CNC-lathe (not shown), comprising a tool holder 1 according to a first embodiment, a parting and grooving tool 2, and a turret 11. The turret 11 is rotatable around a turret axis A1. The turret 11 comprises a front surface 20, an opposite rear surface 21 and a peripheral surface 22 connecting the front and rear surfaces 20, 21. The turret 11 comprises a plurality of tool stations 4. Each tool station 4 comprises a flat surface 24, an opening 25, and a hole pattern (not shown). The tool stations are formed on the peripheral surface 22. The flat surfaces 24 of adjacent tool stations 4a, 4b are spaced apart by a predetermined angle .

(17) The tool holder 1 comprising a mounting portion 5 and a projected portion 6, projecting away from the turret axis A1. The mounting portion 5 comprises a flat surface 7 extending in an interface plane P1. The mounting portion 5 of the tool holder 1 is detachably connected to a tool station 4a. The adjacent tool station 4b is empty, i.e. no cutting tool is connected to the adjacent tool station 4b.

(18) A metal work piece 43 is rotatable around a rotational axis A2, which is parallel to the turret axis A1.

(19) The flat surface 24 of the tool station 4a to which the mounting portion 5 of the tool holder 1 is connected extends in said interface plane P1. The flat surface 24 of said tool station 4a is in contact with the flat surface 7 of the tool holder 1.

(20) The projected portion 6 comprises a recess 13 for holding the parting and grooving tool 2.

(21) The parting and grooving tool 2 is elongated and comprises a cutting portion 8, or a free end portion, and a clamping portion 9. The clamping portion 9 is inside the recess 13.

(22) The parting and grooving tool 2 comprises a parting and grooving blade and a parting and grooving insert.

(23) The cutting portion 9 comprises the parting and grooving insert. The parting and grooving insert comprises a cutting edge 10.

(24) The cutting edge 10 is between the turret axis A1 and the rotational axis A2 of the metal work piece 43.

(25) A longitudinal axis of the parting and grooving tool 2 is extending substantially parallel to a flat surface 24 of an adjacent station 4b to the tool station to which the mounting portion 5 of the tool holder 1 is connected.

(26) As can be seen in FIGS. 2 and 3, the cutting edge 10 and at least a portion of the projected portion 6 are outside a volume limited by a plane comprising the front surface 20 and a plane comprising the rear surface 21.

(27) The CNC-lathe, more specifically the turret 11 is moveable in or around two, preferably three axis. Said axis are designated X, Y and Z, and are orthogonal. The turret 11 is rotatable around the Z axis, which is the turret axis A1. The turret can be set such that the X-axis intersects turret axis A1 and the rotational axis A2 of the metal work piece 43.

(28) Cutting a groove in the metal work piece 43 is achieved by first rotating the tool post 3 including the turret 11 around the turret axis A1 such that a flat surface 24 of one tool station 4b is perpendicular to a shortest line between the turret axis A1 and the rotational axis A2, and such that the tool holder 1 is connected to an adjacent station 4a to the first mentioned tool station 4b. Secondly, the tool post 3 including the turret 11 is moved in a straight line in a feed direction F towards the rotational axis A2 such that a groove is formed in a metal work piece 43. The cutting edge 11 is active, i.e. cuts chips from the metal work piece 43. A groove can be formed which precedes a parting off operation, i.e. a piece of the metal work piece 43 is separated. The feed direction F is along the X-axis. The rotation of the metal work piece 43 is counter clock-wise in FIG. 1.

(29) As seen in e.g. FIG. 1, the adjacent tool station 4b, which is in an active position, is counter-clock-wise in relation to the tool station 4a to which the tool holder 1 is connected, when the front surface of the turret 11 is facing the viewer.

(30) Reference is now made to FIGS. 4-6 which show tool post 3, comprising a cutting tool 1 according to a second embodiment, a parting and grooving tool 2, and a turret 11. The parting and grooving tool 2 and the turret 11 is in accordance with the tool post 3 shown in FIGS. 1-3. The only difference compared to FIGS. 1-3 is the shape of the tool holder 1. The tool holder 1 is connected to a tool station 4a. As can be seen in FIG. 4, the cutting edge 10 intersects or substantially intersects a plane P2 comprising an adjacent tool station 4b and the turret axis A1. More specifically, the cutting edge 10 intersects or substantially intersects a plane P2 comprising the turret axis A1 and rotational axis A2 of the metal work piece 43. A parting and grooving tool axis A3 is inclined in relation to the interface plane P1. The parting and grooving tool 2 is elongated along the parting and grooving tool axis A3.

(31) Reference is now made to FIGS. 7-9 which show the cutting tool 1 according to the second embodiment and the parting and grooving tool 2 shown in FIGS. 1-6. The parting and grooving tool 2 comprises a parting and grooving blade 27 and a parting and grooving insert 28. The parting and grooving blade 27 comprises an insert seat 29 for the parting and grooving insert 28. The parting and grooving blade 27 comprises opposite first and second surfaces 30, 31, opposite third and fourth surfaces 32, 33 and opposite top and rear surfaces 34, 14. The first and second surfaces 30, 31 are side surfaces. During cutting, the third surface 32 is facing towards the rotational axis A2. The parting and grooving insert 28 comprises a cutting edge 10 and a rake face 35,

(32) The top surface 34 of the parting and grooving blade 27 and the rake face 35 are facing the same direction or substantially the same direction.

(33) A parting and grooving tool axis A3 extends parallel to and equidistantly or substantially equidistantly between the opposite third and fourth surfaces 32, 33. The third and fourth surfaces 32, 33 are clamping surfaces. The parting and grooving tool axis A3 extends mid-way between the opposite first and second surfaces 30, 31.

(34) The opposite third and fourth surfaces 32, 33 are V-shaped in a cross section, where said cross section is in a plane perpendicular to the parting and grooving tool axis A3.

(35) The parting and grooving tool 2 is elongated along a parting and grooving tool axis A3. Thus, a distance between opposite top and rear surfaces 34, 14 is greater than a distance between the opposite third and fourth surfaces 32, 33.

(36) As can be seen in FIG. 7, the parting and grooving tool axis A3 is inclined by an angle in relation to the interface plane P1. A distance 15 from the interface plane P1 to the rear end surface 14 of the parting and grooving tool 2 is greater than a distance 16 from the interface plane P1 to the cutting portion 8 of the parting and grooving tool 2.

(37) The mounting portion 5 of the tool holder 1 comprises a flat surface 7 and an external surface 23. The external surface 23 and the flat surface 7 are facing opposite or substantially opposite directions. Through holes in the form of bolt holes (not shown) intersects the flat surface 7 and the external surface 23 of the mounting portion 5. The mounting portion 5 further comprise a shaft 26.

(38) Reference is now made to FIGS. 10-12 which show the tool holder 1 as previously described according to the second embodiment.

(39) The recess 13 comprises first and second side surface 17, 18, a bottom surface 19 and a rear end surface 42. An opening 41 of the recess 13 is opposite the rear end surface 42. The first and second side surfaces 17, 18 of the recess 13 are inclined. In other words, an angle between the bottom surface 19 and the first and second side surface 17, 18, respectively, is acute.

(40) As can be seen in FIG. 10, a shortest distance 39 between the opening 41 of the recess 13 to the interface plane P1 is shorter than a shortest distance 40 from the rear end surface 42 of the recess 13 to the interface plane P1, where the interface plane P1 comprising the flat surface 7. The recess 13, more specifically a line parallel to and mid-way between the first and second side surfaces 17, 18, is inclined in relation to the interface plane P1 by an angle . Said angle is preferably 22.5, 30, 45, 60 or 90. Said angle is preferably 21-90.

(41) The tool holder 1 comprises positioning means 36, 37, i.e. a positioning mechanism, which comprise an adjustment screw 36 for a stop member 37. Said stop member 37 comprises a stop surface 38. Said stop member 37 intersect the rear end surface 42 and the bottom surface 19 of the recess 13. The distance between the opening 41 and the stop surface 38 is adjustable by means of the adjustment screw 36.

(42) The mounting portion 5 comprises a hole pattern, i.e. a set of bolt holes (not shown).

(43) The recess 13 is offset in relation to the flat surface 7 of the mounting portion 5.

(44) Reference is now made to FIG. 13 which show a tool station 4 in a top view. The tool stations 4, 4a, 4b in FIGS. 1-6 may preferably be in accordance with the tool station 4 in FIG. 13. The tool station 4 comprises a flat surface 24, an opening 25, and a hole pattern 44ad, i.e. a set of bolt holes 44a-d. Said opening 25 and bolt holes 44ad are oriented perpendicular to the flat surface 24. Each of said bolt holes 44a-d comprises an internal thread (not shown), corresponding to an external thread of a bolt used for clamping a tool holder to the tool station.

(45) Reference is now made to FIG. 14 which show a mounting portion 5 of a tool holder 1 in a rear view. The above described tool holders may preferably comprise a mounting portion in accordance with the mounting portion 5 in FIG. 14. The mounting portion 5 comprises a hole pattern 45a-d, i.e. a set of bolt holes 45a-d for bolts (not shown). Said bolt holes 45a-d are through holes intersecting the flat surface 7 and are oriented perpendicular to the flat surface 7. The mounting portion 5 comprise a shaft 26 or a pin or boss part, oriented perpendicular to the flat surface 7. The mounting portion 5 comprise a shaft 26 or a pin or boss part or a protrusion, arranged to be inserted into the opening 25 of the tool station 4 seen in FIG. 13. During mounting, the flat surface 7 is in contact with the flat surface of the tool station.