Tool holder with sealed coolant tube

Abstract

To provide a tool holder with a sealed coolant tube.SOLUTION: In a tool holder, between a coolant tube 28 and a smaller-diameter second region 22 of a coolant bore 18, a cavity 30 is formed in a receiving body 6 or a larger-diameter first region 20 in a direction of a receiving section 14. In the tool holder, a bridging element 32, through which a coolant can flow and with which the cavity is sealed against the coolant flow, is disposed in the cavity between the coolant tube and an interface-side end of the smaller-diameter second region, in order to improve the coolant flow and thus improve tool cooling.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a tool holder for holding a tool, in particular a rotary tool, in particular by means of a force fit, and to a kit, in particular for such a tool holder. [Background technology]

[0002] FIG. 5 shows such a tool holder according to the prior art.

[0003] The known tool holder shown in FIG. 5 is what is called a PSC tool holder (a form of shrink fit chuck) which therefore provides at the rear or spindle interface side of the receiving body part of the holder a PSC interface (polygon shank taper, Capto, ISO 26623 spindle interface) for receiving the PSC tool holder in the working spindle (or e.g. a tool turret for non-rotating machining) of a machine tool.

[0004] 5 further illustrates, the receiving body of the PSC tool holder provides a rotation axis, a receiving opening at the front or tool side of the receiving body for press-fittingly holding the rotating tool (where the rotating tool then fits into place in the shrink fit chuck), and a coolant bore disposed along the rotation axis between the PSC interface and the receiving opening, the coolant bore being used to transport coolant from the PSC interface to the receiving opening along the rotation axis.

[0005] As also shown in FIG. 5, the PSC tool holder provides a first region having an adjacent second region toward the receiving opening in the direction of the rotation axis, the diameter of the first region being expanded relative to the diameter of the second region.

[0006] In the case of a PSC tool holder, the coolant tube is threaded into the larger diameter first region of the coolant bore (if the coolant tube can only be threaded to a predetermined depth into the larger diameter first region of the coolant bore) toward the receiving opening such that a cavity is formed in the receiving body or larger diameter first region between the coolant tube and the smaller diameter second region of the coolant bore.

[0007] A drawback of such PSC tool holders or such tool holders forming said cavities is that when coolant is transported through the tool holder, turbulence and bagging of the coolant in the cavity ("containment space") can occur, which can further lead to reduced cooling of the tool. Summary of the Invention [Problem to be solved by the invention]

[0008] The object of the present invention is to improve the above-mentioned tool holders known from the prior art in such a way that they allow improved cooling of the tool. [Means for solving the problem]

[0009] This object is achieved by a tool holder and a kit having the features of the respective independent patent claims.

[0010] Advantageous developments of the invention are the subject of the dependent claims and the following description and relate to a tool holder and a kit.

[0011] Any terms used, such as top, bottom, front, rear, left, or right, unless expressly defined otherwise, are to be understood in the ordinary manner, including with reference to the drawings herein. Terms such as radial and axial, when used, and unless expressly defined otherwise, are to be understood with reference to the axis of rotation (or central axis, or axis of symmetry) of the parts / components described herein, including with reference to the drawings herein.

[0012] The term "substantially," when used, may be understood (as interpreted by the Supreme Court) to mean "practically, but to a significant extent." Thus, the possibility of deviation from the precision implied by this concept may arise unintentionally (i.e., without any functional basis) from manufacturing or assembly tolerances.

[0013] A tool holder for holding a tool, in particular a rotary tool such as an end mill, in particular by means of a force fit, provides a receiving body part.

[0014] The receiving body has a rotation axis, an interface at the rear for receiving a tool holder in a working spindle of a machine tool, a receiving section at the front for holding a tool, in particular a rotary tool, in particular by a press fit, and a coolant bore arranged along the rotation axis between the interface and the receiving section.

[0015] The coolant bore allows or is transported along the axis of rotation from the interface to the receiving section. The coolant can be a gaseous and / or liquid fluid, such as air, CO2, N2, or a gas-liquid mixture (oil mist) used for micro-volume lubrication.

[0016] The coolant bore further provides, toward the receiving section in the direction of the axis of rotation, a first region having an adjacent second region, the diameter of the first region being enlarged relative to the diameter of the second region, or, more simply and specifically, the first region being larger in diameter than the second region.

[0017] The receiving body also has a coolant tube that is disposed within the larger diameter first region of the coolant bore, whereby coolant is transported within or through the interior of the receiving body, or more precisely, within or through the larger diameter second region.

[0018] A cavity is formed in the receiving body, or in the larger diameter first region, in the direction of the receiving section, between the coolant tube and the smaller diameter second region of the coolant bore.

[0019] This cavity is formed in particular because or whenever the coolant tube can only be inserted, in particular screwed, to a limited depth in the larger-diameter first region, in other words the coolant tube can only be inserted, in particular screwed, in the larger-diameter first region here up to its end on the interface side of the smaller-diameter second region.

[0020] The tool holder is distinguished in that coolant can flow therethrough and a bridge element that seals the coolant flow to the cavity is disposed between the coolant tube in the cavity and the interface end of the smaller diameter second region.

[0021] In simple and clear terms, the tool holder bridges the cavity with an intermediate part between the coolant tube and the second region, namely a bridge element (sealed against the cavity 30).

[0022] This has proven to be particularly advantageous as it makes it possible to prevent coolant from flowing from the coolant tube into the cavity.

[0023] The invention is so far based on the idea that coolant flows from a coolant tube into a cavity and through said cavity, causing turbulence and bagging within the cavity.

[0024] For this reason in no small part, the inner diameter of a coolant tube disposed within the larger diameter first region will necessarily be smaller than the diameter of the cavity itself (i.e., the larger diameter first region).

[0025] If the coolant were to flow (virtually seamlessly) from a smaller diameter area to a larger diameter area in this manner, then (in clear and simple terms) the coolant flow, or the coolant, would "divert" into the extended areas to the sides of the cavity, where bagging and turbulence could occur.

[0026] In particular, even in the case of what is called minimum quantity lubrication with oil mist or air-oil mixtures, the oil in the mixture is forced by gravity and rotation into the side regions of the cavity (where it can accumulate), disrupting the coolant flow and changing the composition of the subsequent flow of the coolant mixture.

[0027] However, if the tool holder is such that coolant can flow through it and a bridge element that seals the coolant flow against the cavity is located between the coolant tube in the cavity and the interface end of the smaller diameter second region, the tool holder achieves the effect that the coolant flow is stabilized or kept constant, and the coolant does not flow through the cavity itself, but through the bridge element located therein (so the coolant flow cannot simply "divert" into the larger diameter first region or into the extension region of the cavity). This allows the coolant to flow turbulently and without bagging to the receiving section and therefore to the tool.

[0028] Preferably, even in the case of a press-fit hold, the receiving section can be a receiving opening into which a tool, in particular or for example an end mill, can be pressed / in particular held in a press-fit manner. In such a case, the tool holder can be a clamping chuck, for example a shrink-fit chuck, an expanding hydrochuck or a collet chuck.

[0029] Alternatively, the receiving section can also be a (receiving) pin or the like, on which the tool is held.

[0030] The tool may be a rotary tool or a pivoting tool.

[0031] Also, in order to compensate for the difference in axial length of the cavity to be bridged between the coolant tube and the smaller diameter second region, the bridge element in each case has an individual length which is adjusted to said cavity.

[0032] Preferably, the internal bore of the bridge element has a diameter substantially the same as the diameter of the internal bore of the coolant tube and / or the diameter of the smaller diameter second region of the coolant bore.

[0033] The diameter of the internal bore of the bridge element may also vary, in particular continuously, along the axis of rotation from the interface towards the receiving section, in particular the diameter of the internal bore of the bridge element at the end of the receiving section is substantially the same as the diameter of the smaller diameter second region of the coolant bore.

[0034] That is to say, if the diameters of the inner bore of the coolant tube and the smaller diameter second region differ, the inner bore of the bridge element can therefore adjust to this diameter difference, in particular continuously.

[0035] The bridge element is also substantially hollow cylindrical and has a sealing flange on the front or receiving section side which fits tightly against the rear or interface side of the smaller diameter second region.

[0036] It may further be advantageous if the coolant tube is arranged in a threaded state in the larger diameter first region of the coolant bore, in particular to a predetermined maximum threading depth in the larger diameter first region of the coolant bore.

[0037] A limited screw-in depth can be achieved, for example, from stops, shoulders etc., or even from the thread length alone, or when using a screw-in aid.

[0038] According to a preferred embodiment, it can also be provided that the coolant tube is designed in several parts, comprising at least one supply tube, in particular a threaded bush with an external thread, and a flange element.

[0039] It may also be advantageous for the bridge element to be threadedly or compressed against and held by the flange element of the coolant tube.

[0040] It also appears to be advantageous for the coolant tube to be screwed by means of its threaded bushing into the inside of the receiving body part or into the larger diameter first region of the coolant bore.

[0041] It is also preferred that the flange element is held by being screwed or pressed into the inner bore of the threaded bushing.

[0042] In a preferred embodiment, the bridge element is then made of plastic or rubber or elastomer, or is otherwise made resilient. The bridge element may also be spring-loaded, for example a spring-loaded tube.

[0043] Furthermore, the coolant can be a gas and / or liquid fluid, such as air, CO2, N2, or a gas-liquid mixture (oil mist).

[0044] It also appears to be advantageous for a sealing element to be arranged on the coolant tube and / or on the supply tube, said sealing element sealing the coolant tube and / or supply tube against the larger diameter first region or the threaded bush and / or flange element.

[0045] Preferably, the interface is a PSC interface or an ISO 26623 spindle interface or a KM4X interface.

[0046] Furthermore, it appears to be advantageous for the invention to provide a kit specifically for a tool holder.

[0047] The kit may comprise the aforementioned or a coolant tube, particularly for a tool holder, and a plurality of bridge elements, particularly for the tool holder, the internal bores or internal bores of the respective bridge elements each having a different diameter and / or a different length.

[0048] Furthermore, it can be provided here that the diameter of the internal bore of the bridge elements varies, in particular continuously, along the axis of rotation from the interface to the receiving section, in particular the diameter of the internal bore of each bridge element at the end of its receiving section is substantially the same as the diameter of the smaller diameter second region of the coolant bore.

[0049] The bridge elements may then be interchangeable so that they provide different, and in particular even varying, inner bore diameters to compensate for different differences in the diameter of the coolant tube and the smaller diameter second region.

[0050] The bridge elements can then also be interchangeable, providing they are of different lengths to compensate for differences in the axial length of the coolant tube and the cavity to be bridged by the smaller diameter second region.

[0051] Finally, it can be stated that the present invention is distinguished by all of its aspects, in particular by its simplicity, efficiency and effectiveness, and contributes greatly to improving the flow of coolant and the cooling of tools.

[0052] The description of the preferred embodiments of the present invention includes a number of features which are sometimes reproduced together in the respective dependent claims, however these features may conveniently be considered individually or may be combined into suitable alternative combinations.

[0053] Although certain terms may be used in the specification and / or claims in the singular or in combination with a number in each instance, the scope of the present invention is not intended to be limited to the singular or respective numbers associated with these terms. Furthermore, the words "a" or "an" are not to be understood as numbers but as indefinite articles.

[0054] The foregoing characteristics, features, and advantages of the present invention and the manner in which they are achieved will become more apparent and more clearly understood in connection with the following description of exemplary embodiments of the invention which are described in more detail with reference to the figures / drawings in which like components / parts and features are designated with like reference numerals.

[0055] The exemplary embodiments are used to explain the present invention and do not limit the present invention to the combinations of features, including those relating to functional features, set forth herein. To this end, it is further understood that any suitable feature of each exemplary embodiment may be expressly considered alone, removed from one exemplary embodiment, incorporated into and supplemented by other exemplary embodiments, and combined with any one of the claims. [Brief description of the drawings]

[0056] [Figure 1] 1 illustrates a PSC shrink-fit chuck with an internal feedthrough for cooling lubricant through the tool, according to one embodiment of the present invention. [Diagram 2] 2 shows the PSC shrink-fit chuck according to FIG. 1 in another view. [Diagram 3] 2 shows the PSC shrink-fit chuck according to FIG. 1 in another view. [Figure 4] 2 shows the PSC shrink-fit chuck according to FIG. 1 in another view. [Diagram 5] 1 shows a prior art PSC or Capto tool holder or shrink fit chuck. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0057] -PSC Shrink Fit Chuck 2 with improved internal feed-through of cooling lubricant through the tool (Figs. 1-4) 1-4 show in detail in various views a PSC tool holder 2, in this case in the form of a shrink fit chuck 2, which provides a PSC interface 10 and includes an improved internal feedthrough for cooling lubricant through the tool holder.

[0058] That is, the tool holder 2 (tool holder will hereinafter also be referred to as "holder" 2 for short) shown in Figures 1 to 4 is referred to as a PSC shrink-fit chuck 2, which therefore provides at the rear 12 of the receiving body portion of the PSC shrink-fit chuck 2 a PSC interface 10 (see ISO 26623 spindle interface) for receiving the PSC shrink-fit chuck 2 on a working spindle (or, if machining is performed stationary, for example on a tool turret (not shown) of a machine tool (not shown)).

[0059] The holder 2 shown in Figures 1-4 is distinguished by an improved internal feed-through of cooling lubricant through the tool / holder 2, which will be discussed in more detail below.

[0060] Additionally, as shown in Figures 1-4, the receiving body portion 6 of the holder provides a rotating shaft 8 and a receiving opening 14 at a front portion 16 of the receiving body portion 6 for holding a rotating tool 4 (not shown) by press-fit (the rotating tool 4, e.g. an end mill, is then snapped into place in the shrink fit chuck 2).

[0061] With regard to the described internal feed-through of cooling lubricant, the holder 2 implements a coolant bore 18 disposed along the axis of rotation 8 between the PSC interface 10 and the receiving opening 14. The coolant bore 18 is used to transport coolant or cooling lubricant along the axis of rotation 8 from the PSC interface 10 to the receiving opening 14.

[0062] The coolant bore 18 in the holder 2 or receiving body part 6 or in its interior 54 has various regions, i.e., a first region 20 having an adjacent second region 22 in the direction of the rotation axis 8 towards the receiving opening 14. As shown in Figures 1-4, the diameter 24 of the first region 20 is expanded relative to the diameter 26 of the second region 22.

[0063] In this case, a multi-piece coolant tube 28 consisting of a feed tube 46 , a threaded bushing 48 having external threads 50 , and a flange element 52 is disposed in the first region 20 of the larger diameter 24 of the coolant bore 18 .

[0064] As shown here in Figures 1-4, the coolant tube 28 is screwed by its threaded bushing having male threads 50 above the flange element into the interior 54 of the receiving body part 6 / holder 2 or into the first region 20 of the larger diameter 24 of the coolant bore 18.

[0065] The flange element 52 is pressed and held in the internal bore 56 of the threaded bushing 48 on the receiving opening side. The feed tube is sealed and held in the internal bore 56 of the threaded bushing 48 on the interface side of the threaded bushing 48. This holding also makes it possible to compensate for small angular errors / deviations of the feed tube 46.

[0066] As can also be seen from Figures 1 to 4, the coolant tube 28 is screwed or can be screwed only to a certain depth into the first region 20 of the larger diameter 24 of the coolant bore 18, so that a cavity 30 is formed in the receiving body part 6 or in the first region 20 of the larger diameter 24 between the coolant tube 28 and the second region 22 of the smaller diameter 26 of the coolant bore 18 in the direction of the receiving opening 14.

[0067] With regard to the improved cooling and lubricant internal feedthrough being discussed, the holder 2 implements a bridge element 32 through which the coolant or cooling lubricant can flow and which seals the flow of coolant to the cavity 30 between the coolant tube 28 and the interface end 44 of the second region 22 of the smaller diameter 26.

[0068] The bridge element 32 is substantially hollow cylindrical, elastomeric, and provides a front / receiving opening sealing flange 42 that is resiliently deformable and seals against an interface end 44 of the second region 22 of smaller diameter 26, as shown in Figures 1-4.

[0069] On the interface side, the bridge element 32 is pressed and held against a flange element 52 of the coolant tube 28 .

[0070] As can be seen in Figures 2-4, the internal bore 34 of the bridge element 32 provides a diameter 36 that is substantially the same as the diameter 38 of the internal bore 40 of the coolant tube 28 or its feed tube 46 and as the diameter 26 of the second region 22 of the smaller diameter 26 of the coolant bore 18.

[0071] This means that the coolant or cooling lubricant is supplied to the interior 54 of the holder 2 / receiving body part 6, or to the coolant bore 18 in the interior 54 of the holder 2 / receiving body part 6, along the rotation axis 8 through the holder 2 (on the interface side towards the receiving opening side) with an approximately constant and the same (flow) cross-sectional area.

[0072] The coolant guide or coolant tube 28 and the bridge element 32 are further sealed with respect to the cavity 30 by further sealing means 60, such as a sealing element 60, here in particular a sealing ring 60, at the coolant tube 28, i.e. at the threaded bush 48, at the flange element 52 and at the feed tube 46 of the coolant tube 28.

[0073] The improved cooling lubricant internal feedthrough discussed can be succinctly and clearly explained / expressed as follows: the holder 2 bridges the cavity 30 between the coolant tube 28 and the second region 22 of smaller diameter 26 by means of an intermediate part 32 between the coolant tube 28 and the second region 22 of smaller diameter 26, i.e. by means of a bridge element 32 (sealed against the cavity 30), while keeping the cross-sectional area of ​​the flow constant so that the coolant does not leak.

[0074] Thereby, it is avoided that the coolant or cooling lubricant can flow from the coolant tube 28 into the cavity 30 or there into the expansion area 58 of the cavity 30 or into the first area 20 of the larger diameter 24, and the effect is achieved that the coolant flow is stabilized or kept constant, the coolant flows through the coolant feed with a virtually constant cross-sectional area, due to the use of the bridge element 32. This allows the coolant to be transported or flowed to the receiving section and thus to the tool without turbulence and without bagging.

[0075] Although the present invention has been illustrated and described in more detail by means of preferred exemplary embodiments, the invention is not limited to the disclosed examples, other variants can be derived therefrom without departing from the scope of protection of the invention. [Explanation of symbols]

[0076] Reference Code List 2 Tool holder 4 Tools, Rotate Tool, Rotate Tool 6 Receptor body 8 Rotation Axis 10 Interface 12 Rear 14 Receptor section, receptor opening 16 Front 18 Coolant bore 20 The First Region 22 The Second Region 24 Diameter of the first region (20) 26 diameter of second region (22) 28 (multi-component) coolant tube 30 Cavity 32 (Ceiling) Bridge elements 34 Internal bore of bridge element (32) 36 Diameter of inner bore (34) 38 Diameter of inner bore (40) 40 the inner bore of the coolant tube (28) or of the feed tube (46) 42 (Sealing) Sealing flange of bridge element (32) 44 the interface side end of the second region (22) having a smaller diameter (26) 46 (multi-component) Feed tube for coolant tube (28) 48 (multi-part) threaded bushing for coolant tube (28) 50 Male thread of threaded bush (48) 52 (multi-component) Flange element of coolant tube (28) 54 inside the receiving body part (6) or inside the tool holder (2) 56 Internal bore of threaded bush (48) 58 the first region (20) of larger diameter (24) or the expansion region of the cavity (30) 60 sealing elements / ring

Claims

1. A tool holder (2) for holding a tool (4), in particular a rotary tool (4), in particular by a press fit, comprising a receiving body part (6) having a rotation axis (8), an interface (10) at a rear part (12) for receiving said tool holder (2) in a working spindle of a machine tool, a receiving section (14) at a front part (16) for holding said tool (4), in particular said rotary tool (4), in particular by a press fit, and arranged along said rotation axis (8) between said interface (10) and said receiving section (14), whereby a coolant can be transported from said interface (10) to said receiving section (14) along said rotation axis (8), and a receiving section (14) at a front part (16) for receiving said tool (4), in particular said rotary tool (4), in particular by a press fit, said receiving body part (6) being arranged along said rotation axis (8) between said interface (10) and said receiving section (14), whereby a coolant can be transported along said rotation axis (8) from said interface (10) to said receiving section (14), and a receiving body (6) having a coolant bore (18) with a first region (20) with an adjacent second region (22) toward said receiving section (14), the diameter (24) of said first region (20) being enlarged relative to the diameter (26) of said second region (22), and a coolant tube (28) arranged in said first region (20) of the larger diameter (24) of said coolant bore (18), a cavity (30) being formed in said receiving body (6) or in said first region (20) of the larger diameter (24) in the direction of said receiving section (14) between said coolant tube (28) and said second region (22) of the smaller diameter (26) of said coolant bore (18), a bridge element (32) through which coolant can flow and which seals the flow of coolant to the cavity (30) is disposed between the coolant tube (28) in the cavity (30) and an interface side end (44) of the second region (22) of smaller diameter (26), said bridge element (32) being disposed within the cavity (30).

2. the internal bore (34) of the bridge element (32) has a diameter (36) substantially the same as the diameter (38) of the internal bore (40) of the coolant tube (28) and / or the diameter (26) of the second region (22) of the smaller diameter (26) of the coolant bore (18); A tool holder (2) according to claim 1.

3. a diameter (36) of the internal bore (34) of the bridge element (32) varies in particular continuously along the axis of rotation (8) from the interface (10) towards the receiving section (14), in particular the diameter (36) of the internal bore (34) of the bridge element (32) at the receiving section end is substantially the same as the diameter (26) of the second region (22) of the smaller diameter (26) of the coolant bore (18); A tool holder (2) according to claim 1 or 2.

4. The bridge element (32) is substantially hollow and cylindrical with a front sealing flange (42) which is in flush with the interface end (44) of the second region (22) of smaller diameter (26); A tool holder (2) according to any one of the preceding claims.

5. the coolant tube (28) is threadedly disposed in the first region (20) of the larger diameter (24) of the coolant bore (18), in particular the coolant tube (28) is threadedly disposed in the first region (20) of the larger diameter (24) of the coolant bore (18) to a predetermined maximum threading depth; A tool holder (2) according to any one of the preceding claims.

6. said coolant tube (28) being of multi-part design with at least one feed tube (46), a threaded bush (48) having in particular an external thread (50), and a flange element (52); A tool holder (2) according to any one of the preceding claims.

7. The bridge element (32) is threadedly or compressed to be held against the flange element (52) of the coolant tube (28). A tool holder (2) according to any one of the preceding claims.

8. the coolant tube (28) is screwed by its threaded bushing (48) into the interior (54) of the receiving body portion (6) or into the first region (20) of the larger diameter (24) of the coolant bore (18); A tool holder (2) according to any one of the preceding claims.

9. The flange element (52) is threaded or pressed into and held in the internal bore (56) of the threaded bushing (48). A tool holder (2) according to any one of the preceding claims.

10. The bridge element (32) is a tube made of plastic or rubber or elastomer or is otherwise resilient or spring-loaded. A tool holder (2) according to any one of the preceding claims.

11. the receiving section (14) is a receiving opening (14) for holding a tool (4), in particular a rotary tool (4), in particular by means of a press fit, and / or the tool (4) is a rotary tool (4) or a swivel tool (4), and / or the rotary tool (4) is an end mill (4), A tool holder (2) according to any one of the preceding claims.

12. a sealing element (60) is disposed on the coolant tube (28) and / or on the feed tube (46), the sealing element sealing the coolant tube and / or the feed tube against the first region (20) of larger diameter (24), or against the threaded bushing (48) and / or the flange element (52); A tool holder (2) according to any one of the preceding claims.

13. The interface (10) is a PSC interface or an ISO 26623 spindle interface or a KM4X interface, A tool holder (2) according to any one of the preceding claims.

14. A coolant tube (28), in particular for a tool holder (2) according to any one of claims 1 to 13, and a plurality of bridge elements (32), in particular for a tool holder (2) according to any one of claims 1 to 13, wherein the internal bores (34) of each of said bridge elements (32) have different diameters (36) and / or different lengths, A kit, in particular for a tool holder (2) according to any one of the claims 1 to 13.

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