Tool holder

Abstract

Tool holder (10) for rotating cutting tools with an axis of rotation (R), a body (12) with a receptacle (14) for the rotating cutting tool, wherein the receptacle (14) extends coaxially to the axis of rotation (R), and at least one coolant channel (26) which opens into an opening (28) and is designed to supply coolant to the rotating cutting tool via the opening (28), characterized in that the coolant channel (26) extends through an axial projection (20) and the tool holder (10) has an adjustment mechanism (34) which can be adjusted between a first position in which the opening (28) is spaced at a first radial distance (r1) from the axis of rotation (R), and a second position in which the opening (28) is spaced at a second, different radial distance (r2) from the axis of rotation (R).wherein the axial projection (20) is elastically deflected in the second position relative to the first position by the adjustment mechanism (34).

Description

[0001] The invention relates to a tool holder for rotating cutting tools with an axis of rotation, a body with a holder for the rotating cutting tool, wherein the holder extends coaxially to the axis of rotation, and wherein at least one coolant channel opens into an opening and is designed to supply coolant to the rotating cutting tool via the opening.

[0002] Such tool holders are known from the prior art.

[0003] When coolant is supplied through the face of a tool holder, it is driven radially away from the cutting edge of the rotating cutting tool by centrifugal forces. The nozzle formed by the coolant channel opening can only be optimized for a specific combination of length and cutting speed, particularly when tools of different lengths or different cutting speeds are to be used in the same tool holder.

[0004] Tool holders are shown in DE 10 2014 211 412 B3, DE 10 2004 044 267 A1, DE 43 08 500 A1, DE 42 18 879 A1, DE 82 12 073 U1 and DE 28 38 434 A1.

[0005] The aim of the invention is to provide a tool holder for rotating cutting tools that can effectively supply coolant to the rotating cutting tool over a wide range of cutting speeds and tool lengths.

[0006] To achieve this goal, the invention provides a tool holder for rotating cutting tools, comprising an axis of rotation, a body with a receptacle for the rotating cutting tool, wherein the receptacle extends coaxially to the axis of rotation, and at least one coolant channel which opens into an opening and is designed to supply coolant to the rotating cutting tool via the opening.

[0007] The coolant channel extends through an axial projection and the tool holder has an adjustment mechanism that can be adjusted between a first position in which the opening is spaced at a first radial distance from the axis of rotation and a second position in which the opening is spaced at a second, different radial distance from the axis of rotation, wherein the axial projection in the second position is elastically deflected relative to the first position by the adjustment mechanism.

[0008] This adjustment mechanism for improving cooling performance allows for a change in the orientation of the nozzle formed by the opening of the coolant channel, thus enabling an adjustment of the coolant jet direction to different cutting speeds and tool lengths.

[0009] In one embodiment of the invention, the projection has an axial length of at least 4 mm, in particular at least 9 mm. This makes the projection sufficiently long to allow it to be elastically deflected over a large radial distance by the adjustment mechanism. This allows the alignment, in particular the angle to the axis of rotation of the coolant jet, to be adjusted over a wide range.

[0010] According to one aspect of the invention, the difference between the first radial distance and the second radial distance is at least 0.02 mm, in particular at least 1 mm. Additionally or alternatively, the difference between the first radial distance and the second radial distance is at most 5 mm, in particular at most 1 mm. This covers a suitable range of cutting speeds and tool lengths.

[0011] In a further embodiment of the invention, a coolant channel section adjacent to the opening extends in the first position at a first angle to the axis of rotation and in the second position at a second angle to the axis of rotation, wherein the difference between the first angle and the second angle is at least 4 degrees. The coolant channel section adjacent to the opening defines the direction of the coolant exiting through the opening. With a difference of at least 4 degrees between the first angle and the second angle, a wide range of coolant jet directions is therefore possible.

[0012] In a further embodiment of the invention, the tool holder has a plurality of coolant channels, each extending through its own projection. To improve cooling performance, a plurality of coolant nozzles are provided during operation. Furthermore, with a plurality of coolant jets, several different areas of the rotating cutting tool can be cooled simultaneously, particularly if the angle to the axis of rotation differs between the coolant jets or the coolant channel sections adjacent to the opening.

[0013] According to a further aspect of the invention, the projections around the receptacle are spaced apart from each other in the circumferential direction, in particular uniformly, i.e., the distance between two adjacent projections is always the same. This allows the cooling performance to be increased.

[0014] According to a further embodiment of the invention, the adjusting mechanism comprises a sleeve-shaped adjusting element which, in the first position, is arranged in a first axial position and, in the second position, in a second axial position relative to the body. In the first and second positions, the adjusting element presses the axial projections radially inwards by radially different amounts, the axial adjustment preferably changing the radial deflection of the axial projections continuously. The adjusting mechanism is thus simple and compact in design, such that all axial projections can be adjusted simultaneously by the adjusting element.

[0015] In a further embodiment of the invention, the adjustment mechanism comprises a locking mechanism that locks the adjustment element in a selected position, e.g. the first position or the second position, in order to hold the adjustment element in place during operation.

[0016] In one embodiment of the invention, the difference between the first axial position and the second axial position is between 0.5 and 7 mm, thereby providing a sufficient range for adjusting the alignment of the coolant jets over a large area.

[0017] According to another aspect of the invention, the adjusting element has an inner adjusting surface which, in the first and second positions, bears against an outer adjusting surface of the axial projection, wherein the inner adjusting surface and / or the outer adjusting surface extend at an angle to the axis of rotation of between 2 and 45 degrees. This embodiment offers the advantage that the axial projections can be effectively deflected elastically.

[0018] In a further embodiment of the invention, the inner adjustment surface and / or the outer adjustment surface each have an axial length that is between 15 and 35% of the axial length of the projection and thus covers a length sufficient for effective deflection of the projection.

[0019] Each individual feature of the embodiments disclosed above can be part of one of the embodiments disclosed above and thus form a further embodiment of the invention. In other words, any or all of the individual features disclosed above can be combined in a further embodiment of the invention.

[0020] The foregoing aspects and many of the associated advantages of the claimed subject matter will become apparent with increasing understanding through the following detailed description in conjunction with the accompanying drawings, wherein: - Fig. Figure 1 shows a schematic representation of a tool holder according to the invention in an exploded view; - Fig. 2 a schematic representation of the tool holder of Fig. 1 shows in a sectional view; - Fig. 3 a schematic representation of section B of Fig. Figure 2 shows an adjustment mechanism of the tool holder in a first position; and - Fig. 4 a schematic representation of section B of Fig. Figure 2 shows the adjustment mechanism in a second position.

[0021] Fig. Figure 1 shows a schematic representation of a tool holder 10 with a body 12 and a holder 14 for a rotating cutting tool (not shown).

[0022] The tool holder 10 is made of tool steel.

[0023] In one embodiment, the tool holder 10 is a shrink-fit chuck or a hydraulic chuck.

[0024] Recording 14 (see Fig. 2) extends from an end face 16 of the body 12 coaxially to an axis of rotation R in the direction of a rear end 18 of the body 12, the rear end 18 forming a coupling section for coupling the tool holder 10 to a machine spindle.

[0025] The tool holder 10 also has several finger-like projections 20 that extend in axial direction A from a shoulder 22 of the body 12 to the front surface 16.

[0026] The axial length P (see Fig. 3) The projections 20 are at least 4 mm.

[0027] In an alternative embodiment, the axial length P of the projections 20 is at least 9 mm.

[0028] In the illustrated embodiment, the tool holder 10 has six projections 20.

[0029] In an alternative embodiment, the tool holder 10 can have any number of projections 20, in particular between one and twelve.

[0030] The projections 20 are arranged circumferentially around the receptacle 14 and radially spaced from a section 24 of the body 12 surrounding the receptacle 14 at the end face 16.

[0031] Furthermore, the projections can be 20, as in Fig. 1 shown, are equally spaced from each other.

[0032] In the embodiment shown, the projections 20 are formed integrally with the body 12.

[0033] In an alternative embodiment, the body 12 and at least one of the projections 20 can be formed by separate parts.

[0034] The body 12 and / or the projections 20 can be manufactured by additive manufacturing such as 3D printing.

[0035] The projections 20 each have an internal coolant channel 26 (see Fig. 4) extending from an opening 28 at the distal end 30 of the projection 20 into the body 12 and in fluid communication with a coolant supply (not shown in the figures).

[0036] It should be noted that this means that the coolant channels 26 do not end at the shoulder 22, as shown in the figures which only schematically depict the tool holder 10.

[0037] The coolant channel section 32 opening into the opening 28 (see Fig. 3) of the coolant channel 26 forms a nozzle through which, during operation of the tool holder 10, coolant is sprayed in the form of a coolant jet onto a section of the rotating cutting tool.

[0038] In the illustrated embodiment, the projections 20 are identical.

[0039] In an alternative embodiment, however, the projections 20 and / or the respective coolant channels 26 can also be formed individually, in particular to provide nozzles with different orientations, i.e., nozzles directed towards different axial sections of the rotating cutting tool.

[0040] To adjust the orientation of the nozzles, the tool holder 10 has an adjustment mechanism 34, which can be set between a first position (see Fig. 3) and a second position (see Fig. 4) is adjustable.

[0041] The adjustment mechanism 34 has a sleeve-like adjustment element 36 which is arranged in a first axial position relative to the body 12 in the first position and in a second axial position relative to the body 12 in the second position.

[0042] The difference D between the first axial position and the second axial position is 3 mm.

[0043] In an alternative embodiment, the difference D between the first axial position and the second axial position is between 0.5 and 7 mm.

[0044] The sleeve-like adjusting element 36 can be a lock nut that is connected to the body 12 via a thread to ensure a stable position.

[0045] For example, the shoulder 22 can have an external thread and the adjusting element 36 a corresponding internal thread.

[0046] However, other locking mechanisms with the same effect are also conceivable.

[0047] In an alternative embodiment, in which the tool holder 10 has in particular only a single projection 20 or a few projections 20, the adjusting mechanism 34 and / or the adjusting element 36 may be designed differently, as long as the adjusting mechanism 34 has the same functions listed below for the embodiment presented here.

[0048] The adjusting element 36 is designed such that it elastically deflects the projections 20 radially inwards, i.e. towards the axis of rotation R, when the adjusting element 36 is moved against the axial direction A towards the shoulder 22.

[0049] For this purpose, the adjusting element 36 has an inner adjusting surface 38 and the axial projections 20 each have a corresponding outer adjusting surface 40, which lie against each other between the first and the second position.

[0050] The outer adjustment surfaces 40 extend from the distal ends 30 and have an axial length F which is between 15 and 35% of the axial length P of the projections 20.

[0051] The inner adjustment surface 38 extends from a front end 42 of the adjustment element 36 and has an axial length f which is between 15 and 35 % of the axial length P of the projections 20.

[0052] In the illustrated embodiment, the inner adjustment surface 38 and the outer adjustment surfaces 40 are formed by a chamfer extending at an angle β of 10 degrees to the axis of rotation R.

[0053] In an alternative embodiment, the inner adjustment surface 38 and / or the outer adjustment surfaces 40 extend at an angle β of 2 to 45 degrees to the axis of rotation R.

[0054] In an alternative embodiment, the inner adjustment surface 38 and the outer adjustment surfaces 40 can be configured differently. For example, the inner adjustment surface 38 and the outer adjustment surfaces 40 can have chamfers with different angles β. Additionally or alternatively, the inner adjustment surface 38 and / or the outer adjustment surfaces 40 can be configured without chamfers.

[0055] In the first position, the openings 28 are spaced apart at a first radial distance r1 from the axis of rotation R, and in the second position, the openings 28 are spaced apart at a second radial distance r2 from the axis of rotation R, where the second radial distance r2 is smaller than the first radial distance r1.

[0056] The difference between the first radial distance r1 and the second radial distance r2 can be at least 0.02 mm, in particular at least 1 mm.

[0057] Furthermore, the difference between the first radial distance r1 and the second radial distance r2 can be at most 5 mm, in particular at most 1 mm.

[0058] In the first position, the coolant channel sections 32 extend at a first angle α1 to the axis of rotation R. In the second position, the coolant channel sections 32 extend at a second angle α2 to the axis of rotation R.

[0059] The first angle α1 and / or the second angle α2 can each be between 2 and 45 degrees.

[0060] In one embodiment, the difference between the first angle α1 and the second angle α2 is between 0.1 and 15 degrees.

[0061] In another embodiment, the difference between the first angle α1 and the second angle α2 is at least 4 degrees.

[0062] In the embodiment shown here, the adjusting element 36 deflects the projections 20 radially inwards elastically by radial amounts that continuously increase when the adjusting element 36 is moved from the first position to the second position.

[0063] The angle of the coolant channel sections 32 therefore decreases continuously from an angle α1 to an angle α2 when the adjusting element 36 is moved from the first position to the second position.

[0064] In this way, a tool holder 10 is provided for rotating cutting tools, the adjustment mechanism 34 of which makes it possible to adjust the direction of the nozzles so that coolant can be supplied to the rotating cutting tool effectively over a wide range of cutting speeds and tool lengths.

Claims

[1] Tool holder (10) for rotating cutting tools with an axis of rotation (R), a body (12) with a receptacle (14) for the rotating cutting tool, wherein the receptacle (14) extends coaxially to the axis of rotation (R), and at least one coolant channel (26) which opens into an opening (28) and is designed to supply coolant to the rotating cutting tool via the opening (28), characterized by, that the coolant channel (26) extends through an axial projection (20) and the tool holder (10) has an adjustment mechanism (34) which can be adjusted between a first position in which the opening (28) is spaced at a first radial distance (r1) from the axis of rotation (R) and a second position in which the opening (28) is spaced at a second, different radial distance (r2) from the axis of rotation (R), wherein the axial projection (20) is elastically deflected by the adjustment mechanism (34) in the second position relative to the first position. [2] Tool holder (10) according to claim 1, characterized by , that the projection (20) has an axial length (P) of at least 4 mm, in particular of at least 9 mm. [3] Tool holder (10) according to claim 1 or 2, characterized by, that the difference between the first radial distance (r1) and the second radial distance (r2) is at least 0.02 mm, in particular at least 1 mm, and / or at most 5 mm, in particular at most 1 mm. [4] Tool holder (10) according to one of the preceding claims, characterized by , that a coolant channel section (32) adjacent to the opening (28) extends in the first position at a first angle (α1) to the axis of rotation (R) and in the second position at a second angle (α2) to the axis of rotation (R), wherein the difference between the first angle (α1) and the second angle (α2) is at least 4 degrees. [5] Tool holder (10) according to one of the preceding claims, characterized by , that the tool holder (10) has a plurality of coolant channels (26), each extending through its own projection (20). [6] Tool holder (10) according to claim 5, characterized by, that the projections (20) around the receptacle (14) are spaced apart from each other in the circumferential direction, in particular uniformly. [7] Tool holder (10) according to claim 5 or 6, characterized by , that the adjusting mechanism (34) has a sleeve-like adjusting element (36) which is arranged in a first axial position in the first position and in a second axial position relative to the body (12), wherein the adjusting element (36) in the first and second positions presses the axial projections (20) radially inwards by radially different amounts, wherein the axial adjustment preferably continuously changes the radial deflection of the axial projections (20). [8] Tool holder (10) according to claim 7, characterized by , that the difference (D) between the first axial position and the second axial position is between 0.5 and 7 mm. [9] Tool holder (10) according to claim 7 or 8, characterized by, that the adjusting element (36) has an inner adjusting surface (38) which in the first and second positions rests against an outer adjusting surface (40) of the axial projection (20), wherein the inner adjusting surface (38) and / or the outer adjusting surface (40) extend at an angle (β) to the axis of rotation (R) which is between 2 and 45 degrees. [10] Tool holder (10) according to claim 9, characterized by , that the inner adjustment surface (38) and / or the outer adjustment surface (40) each have an axial length (f, F) which is between 15 and 35 % of the axial length (P) of the projection (20).

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