Chucking device for chucking an object, especially a tool

Abstract

To provide a chucking apparatus for chucking an object and a tool in particular.SOLUTION: A chucking nut 19 has a plurality of particularly-cylindrical rolling bodies 35 having a predetermined rolling body engagement structures. The rolling bodies are held on a sleeve-type chucking body 21 rotatably in an axial direction, which are dispersed and arranged in a circumferential direction in the chucking nut, or the plurality of particularly-cylindrical rolling bodies having the predetermined rolling body engagement structure are held and arranged in the nut rotatably in the axial direction. In particular, the rolling bodies are dispersed and arranged in the circumferential direction between the sleeve-type chucking body and a base body. At least one base body engagement structure is formed in the base body, and the rolling bodies are engaged with the at least one base body engagement structure of the base body by the rolling body engagement structure of the rolling body or can be engaged with the structure. The chucking nut can be screwed onto the base body and can be twisted off from the base body, by rolling of the rolling bodies on the base body by an engagement structure in which the rolling bodies engage with each other.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The invention relates to a chucking device for chucking an object according to the preamble of patent claim 1, a tool holder for a machine tool having a chucking device according to patent claim 13, and a machine tool having a tool holder according to patent claim 15. [Background technology]

[0002] Several mechanisms are known for non-rotatably chucking a tool, such as a milling tool, in a tool holder of a machine tool. The tool can be chucked, for example, by a collet chuck provided on the tool holder. Conventionally, this type of collet chuck includes a radially elastic collet having an outer cone. The collet is disposed in a receiving space in a base of the tool holder, which receiving space forms an inner cone. The collet disposed in the receiving space is pressed into the receiving space by a chucking nut of the collet chuck, which may be threadable into the base. The collet is radially compressed under the action of the conical surface of the outer cone of the collet and the conical surface of the inner cone of the base, and the tool is chucked with its tool shank disposed in the tool receiving space of the collet.

[0003] A tool holder with a collet chuck is known, for example, from US Pat. No. 5,649,999.

[0004] In order to chuck a tool with a collet chuck so that it cannot rotate as desired, it has been necessary to form the thread pitch of the chucking nut and the corresponding thread pitch of the base body small, so that the relatively large axial force required to press the collet into the receiving space of the base body can be realized with little effort, and can be realized while manually rotating the chucking nut.

[0005] However, due to the small thread pitch, the threading distance when the chucking nut is screwed into the base is relatively long. In addition, when the chucking nut is screwed into the base, due to the small thread pitch, high frictional forces must be overcome over the long threading distance. Furthermore, conventional collet chucks typically achieve a smaller chucking force for chucking a tool than other chucking systems, especially compared to interference-fit chucks.

[0006] For these reasons, the chucking area of ​​conventional collet systems is limited to smaller tool diameters. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] German Patent Application Publication No. 10 2015 002 943A1 [Patent Document 2] German Patent Application Publication No. 10 2016 110 087A1 Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a chucking device for chucking an object, in particular a tool, which can chuck the object with a large chucking force simply and effectively.

[0009] The above object is achieved by the features of the independent claims. Preferred developments are disclosed in the dependent claims. [Means for solving the problem]

[0010] According to patent claim 1, a chucking tool for chucking an object, in particular a tool, is proposed, which comprises a base body having a receiving space, in particular a cylindrical or conical space, in which the object can be placed, and the chucking device comprises a chucking nut that can be screwed onto the base body, and by screwing the chucking nut onto the base body, the object placed in the receiving space can be chucked so that it cannot rotate.

[0011] According to the present invention, the chucking nut has a plurality of rolling elements, particularly cylindrical, having a predetermined rolling element engagement structure, and the rolling elements are held axially rotatably by a chucking body, particularly a sleeve-type chucking body, of the chucking nut and are arranged in a dispersed manner in the circumferential direction of the chucking nut.

[0012] Alternatively, according to the present invention, a plurality of rolling elements, particularly cylindrical rolling elements, having a predetermined rolling element engagement structure are also provided, and the rolling elements are axially rotatably held and arranged, and are circumferentially distributed between the chucking nut's, particularly sleeve-type, chucking body and the base body.

[0013] Clearly and simply stated, both alternatives according to the present invention provide a plurality of, in particular cylindrical, rolling elements having a predetermined rolling element engagement structure, which are in principle held and arranged so as to be axially rotatable within this range, and are distributed circumferentially between the chucking nut or the chucking body of the chucking nut and the base. The first-mentioned alternative considers or shows that the rolling elements are part of the chucking nut, while the second-mentioned alternative considers or shows that the rolling elements are separate components arranged between the chucking nut or the chucking body of the chucking nut and the base.

[0014] In addition, at least one base engagement structure is formed on the base of the tool holder, and the rolling elements are engaged or can be engaged with the at least one base engagement structure of the base by the rolling element engagement structure of the rolling elements. Furthermore, the chucking nut can be screwed onto or unscrewed from the base by the mutually engaging engagement structures, in particular by the rolling elements rolling on the base.

[0015] This allows objects to be chucked easily and efficiently with a large chucking force, because in the configuration according to the present invention, the chucking nut does not contact or engage with the base body along its entire circumference, but only contacts or engages with the rolling elements that are held axially rotatably. Therefore, the frictional force acting when the chucking nut is screwed into the base body is significantly reduced. Furthermore, only rolling friction needs to be overcome, and sliding friction, as in conventional threads, does not need to be overcome. As a result, the thread can be configured so that the chucking force for chucking an object placed in the receiving space is effectively increased while the effort required to rotate the chucking nut remains the same. Therefore, even objects with large diameters can be reliably chucked.

[0016] In a preferred refinement of the chucking tool according to the invention, the base-engagement structure is formed by a screw thread having at least one encircling thread groove, which forms at least one web extending spirally around the base. The chucking nut can be screwed onto the base in a functionally reliable manner via a screw thread designed as a conventional male screw. In addition, such a male screw thread can be particularly easily manufactured.

[0017] The thread here is preferably designed as a multiple-start thread, and in particular the number of thread leads corresponds to the number of rolling elements held on the chucking nut or between the chucking nut and the base body, so that the chucking nut can be screwed onto and unscrewed from the base body particularly simply and functionally reliably.

[0018] However, alternatively, the thread may be formed by a single thread.

[0019] In an alternative preferred refinement, it may be provided that a plurality of engagement regions, particularly distributed circumferentially and / or spaced apart from one another, each having a base engagement structure, are formed on the base, and the rolling elements are engaged or can be engaged with the base engagement structure of the base by the rolling element engagement structure of the rolling elements. The chucking nut can then be screwed onto or unscrewed from the base by the engagement structure in which the rolling elements and the base are engaged with one another, particularly by the rolling elements rolling on the base. Thus, the axially rotatably held rolling elements, combined with the circumferentially distributed engagement regions of the base, significantly increase the degree of freedom in designing the thread for screwing the chucking nut onto the base, making it possible to chuck objects particularly simply and effectively. This allows the thread to be effectively optimized for chucking an object placed in the receiving space of the base. In particular, the chucking nut can be screwed onto the base with a significantly reduced threading distance.

[0020] Preferably, the base engagement structure of each base engagement region is formed by a plurality of surrounding grooves spaced apart from one another, particularly in the axial direction, which form a web extending outwardly around the periphery of the base. The chucking nut can be simply and reliably screwed onto and unscrewed from the base by such a base engagement structure. It is preferably provided herein that the base webs of each engagement region extend parallel to one another.

[0021] The grooves in each base engagement region preferably form a base thread. The base thread allows the chucking nut to be effectively screwed in and out via the rolling elements engaged with the thread. Here, each base thread extends from a start region to an end region when viewed in the circumferential direction. Here, it is preferable that the thread pitch of each base thread varies, particularly decreases, from the initial region toward the end region. By varying the thread pitch, chucking of an object placed in the receiving space of the base can be effectively optimized. In particular, it is advantageous to reduce the thread pitch. As a result, when the chucking nut is screwed into the base, the rolling elements can initially guide the chucking nut through a region with a large thread pitch, so that the chucking nut covers a relatively large axial distance in a short screwing distance. In this thread region, the chucking force applied by the chucking nut to chuck an object placed in the receiving space is relatively small, so the effort required to screw the chucking nut is small despite the large thread pitch. Subsequently, the chucking nut can be guided by its rolling elements through a region with a significantly reduced thread pitch. In this way, in the threaded region, the chucking nut can apply a maximum chucking force to chuck an object placed in the receiving space. Furthermore, due to the small thread pitch, the chucking nut can be screwed into the base with relatively little effort.

[0022] The base thread formed here on the engagement region can preferably be introduced into the base by means of a thread milling or grinding machine.

[0023] In a preferred specific refinement, when viewed in a top view of the base body, each base thread has a continuously or partially curved profile. As a result, a continuous change in the thread pitch of the base thread and thus a particularly simple and functionally reliable screwing of the chucking nut into the base body can be achieved. Alternatively or additionally, each base thread can have multiple, in particular two, pitch sections with different constant thread pitches. In this way, a variable thread pitch can be used particularly simply. Here, it is preferred that a transition region with a continuously changing thread pitch is provided between regions with a constant thread pitch.

[0024] The rolling element engagement structure of each rolling element is preferably formed by a plurality of surrounding grooves spaced apart from one another in the axial direction of the rolling element, the plurality of surrounding grooves forming an annular web extending circumferentially around each rolling element. This configuration of the rolling element engagement structure allows the chucking nut to be simply and functionally reliably screwed onto and unscrewed from the base.

[0025] Furthermore, it may be advantageous if the sides of the web are spherical, which allows a large bearing surface for forces to be achieved.

[0026] Alternatively, the rolling element engagement structure itself may be configured as a continuous (external) thread, the pitch direction of which corresponds to the pitch direction of the base thread. This configuration increases the axial chucking distance when the chucking nut is tightened. The flank of the thread may also be spherical.

[0027] In a preferred specific refinement, each rolling element has a bearing journal, particularly a cylindrical one, protruding from an end side or end wall of the rolling element, and each rolling element is axially rotatably held in a chucking body of the chucking nut by the bearing journal. Thus, the rolling elements can be reliably and effectively held axially rotatably, i.e., rotatably held on the chucking nut around its longitudinal axis. Here, the rolling elements can be held in the chucking body directly or indirectly, or via at least one connecting element.

[0028] More preferably, each rolling element is axially rotatably mounted to an annular, especially circular, bearing cage of the chucking nut, especially by a bearing journal. Via such a bearing cage, the rolling elements can be easily fastened to the chucking nut or the sleeve-type chucking body of the chucking nut at predetermined circumferential distances from one another, axially rotatably. Preferably, the annular bearing cage is formed of a plurality of sections, especially of rectangular cross-section ring segment elements, and at least one rolling element is assigned to at least one of the ring segment elements. This significantly simplifies the mounting of the bearing cage to the chucking nut. It is particularly preferred that a single rolling element is assigned to each ring segment element.

[0029] The rolling elements are also preferably housed in a bearing cage, in particular a window-type cage with pockets for the rolling elements.

[0030] Thus, bearing cages, especially window-type cages, can keep the rolling elements separated from each other to avoid contact with each other, and can keep the rolling elements at the same distance, allowing for more even load distribution.

[0031] Here, the rolling elements can be accommodated in the pockets of the window-type cage with a large axial play to optionally facilitate screwing in the bearing cage with the rolling elements, or alternatively the axial length of the pockets of the window-type cage can substantially correspond to the axial length of the rolling elements, as a result of which more accurate guiding is optionally possible.

[0032] Furthermore, it may be advantageous for selected pockets of the window cage to have an axial offset relative to other pockets of the window cage, in particular for each pocket to have an axial offset relative to its respective neighboring pocket.

[0033] Here, the offset of the pocket can be adapted to the thread pitch of the base engagement structure and / or the thread pitch of the chucking body engagement structure of the sleeve-type chucking body, and this thread pitch allows the chucking body engagement structure of the chucking body to be engaged with the rolling body engagement structure of the rolling body and / or to be adapted to the number of rolling bodies.

[0034] Particularly preferably, in each case, adjacent circumferentially surrounding pockets have an axial offset, and the axial offset is adapted to the thread pitch of the base engagement structure and / or the thread pitch of the chucking body engagement structure, as well as the number of rolling bodies.

[0035] The adaptation can be preferably made in such a way that, when all pockets are uniformly distributed in the circumferential direction on the bearing cage, and when the rolling element engagement structures of the rolling elements are not themselves threaded, the size of the axial offset between two adjacent pockets in each case is the same, and / or the total offset of all pockets on the periphery of the bearing cage corresponds to the thread pitch of the base engagement structure and / or the chucking body engagement structure. The advantage that can be achieved with such a configuration is that the bearing cage with the rolling elements arranged therein can be easily and reliably screwed into the engagement structures (of the chucking body and the base).

[0036] The sleeve-type chucking body preferably has a chucking body engagement structure, which engages the chucking body with the rolling body engagement structure of the rolling body, thereby realizing effective transmission of the chucking force in the axial direction from the rolling body to the chucking nut and effective guiding of the rolling body in the circumferential direction.

[0037] Here, the chucking body engagement structure is preferably formed by a plurality of surrounding grooves spaced apart from one another, particularly in the axial direction, and the plurality of surrounding grooves form an annular web extending circumferentially inward around the chucking body.

[0038] However, it may also be provided that the chucking body engagement structure is formed by a screw thread having at least one surrounding thread groove, where the thread groove may be formed by at least one web extending spirally inwardly in the circumferential direction (U) around the chucking body.

[0039] Here, it can also be provided that the thread has multiple leads, in particular the number of thread leads corresponding to the number of rolling elements.

[0040] Such a chucking body engagement structure allows the chucking nut to be screwed onto and unscrewed from the base simply, functionally and reliably.

[0041] However, particularly when the rolling elements have (external) threads, it is preferred that the chucking body engagement structure has an internal thread corresponding to the external rolling element threads (and / or the base body engagement structure has an external thread corresponding to the external rolling element threads), such that the mentioned components can be screwed / unscrewed relative to each other simply and functionally reliably.

[0042] The chucking body engaging structure may also be provided to be disposed on an inner wall region surrounding the sleeve-type chucking body (21) in the circumferential direction (U).

[0043] In a particular refinement, the sleeve-type chucking body here has a recess or depression extending circumferentially inside, in which the annular bearing cage can be arranged so as to match its contour. Thus, the bearing cage can be simply and effectively connected to the chucking body. Here, the bearing cage arranged in the recess is preferably held in the sleeve-type chucking body so as to be rotatable relative to the chucking body in the circumferential direction. Preferably, a wall region of the sleeve-type chucking body that bounds the recess on the base side can form a chucking body engagement structure.

[0044] In further embodiments, the distance between the grooves of the chucking body engagement structure and / or the rolling element engagement structure and / or the base engagement structure can be adapted so that, when a large axial force is applied and the components are deformed as a result, a uniform wear pattern occurs between the mutually assigned engagement structures. In particular, the distance between the grooves of the chucking body engagement structure and / or the distance between the grooves of the base engagement structure can be selected to be smaller than the distance between the grooves of the rolling element engagement structure.

[0045] In a preferred specific refinement, the chucking device has a radially elastic collet arranged in the receiving space and having an outer cone, said collet being able to be pressed into the receiving space of the base body by a chucking nut, said receiving space forming an inner cone, so that an object arranged in the object receiving space of the collet, in particular a cylindrical object receiving space, is chucked non-rotatably.

[0046] In particular, an annular connecting element is further provided, via which the chucking nut can be releasably connected to the collet, and in particular the annular connecting element is connected to the sleeve-type chucking body of the chucking nut so as to be axially rotatable by a rolling bearing. Such a configuration allows particularly reliable chucking and release of an object such as a tool shank in the collet, even in the case of an extremely large chucking force.

[0047] It may also be provided here that the annular connecting element may be connected or locked to the collet by a locking device, in particular a bayonet lock, with the advantage that the collet may be changed when it is removed without the need to unscrew the chucking nut from the base.

[0048] Furthermore, anti-twist means may be provided between the collet and the base, said anti-twist means being formed in particular by complementary engagement points on the axial extensions of the collet and the base.

[0049] Such a collet chuck can be used particularly simply and quickly to chuck objects such as tool shanks, where the collet can be changed particularly simply and quickly thanks to the particularly short threading path of the chucking nut that can be realized by the structure according to the invention.

[0050] In an alternative improved form of the chucking device, it can also be provided that the chucking nut has a sleeve-type cone connected to the chucking body and has an inner cone wall area forming an inner cone, and when the chucking nut is screwed onto the base, the cone comes into particular flat contact with the receiving portion of the base by the inner cone wall area, the receiving portion forms a receiving space, and the receiving portion is pressed inward, particularly in a radial direction, against an object placed in the receiving space, thereby chucking the object so that it cannot rotate.

[0051] In particular when such cones are used, the base body may also preferably have slots here, which may be formed through the cone or as notches in the cone.

[0052] This allows the object to be chucked simply and effectively without the use of a collet. In this embodiment, the use of a cylindrical intermediate sleeve also makes it possible to adapt the receiving part to different object diameters, in particular tool shank diameters.

[0053] The base body preferably has an end stop that contacts the chucking nut when it is screwed into the base body. This effectively prevents unwanted over-rotation of the chucking nut, and a functionally reliable configuration can be realized. Preferably, the end stop is formed by at least one wall region on the end side of the base body or is oriented on the end side. Alternatively, the end stop can also be formed by at least one wall region of the base body, and the wall region can bound the base body engagement region in the circumferential direction.

[0054] The chucking device preferably includes a clamping device for clamping the chucking nut when the chucking nut is screwed onto the base. The sleeve-type chucking body includes an annular, particularly thin-walled, clamping web of the clamping device, which protrudes from the end wall of the chucking body, particularly in the axial direction of the tool holder, and which makes particularly flat contact with the corresponding clamping wall area when the chucking nut is screwed onto the base. This effectively prevents unwanted rotation of the chucking nut relative to the base. The clamping wall area may be formed, for example, by an annular shoulder that protrudes particularly radially outward from the base. Alternatively, the clamping wall area may also be formed by at least one, particularly annular, clamping element, which is fixed to the base and elastic in the axial direction of the tool holder, allowing tension to be applied through the chucking nut by screwing it in and the tension to be released by unscrewing the chucking nut. This type of clamping element may be formed, for example, by a disc spring or an O-ring.

[0055] More preferably, the chucking nut can be removed from or attached to the base body. Each base body engagement region can be assigned a receiving groove in the base body, which particularly extends in the axial direction and / or corresponds to the contour of the rolling elements, and the rolling elements are introduced into the receiving groove by their peripheries when the chucking nut is attached to the base body. Each base body engagement region is circumferentially adjacent to the associated receiving groove. Such a receiving groove allows the chucking nut to be particularly easily and quickly screwed on or unscrewed.

[0056] Preferably, the receiving portion of the base body forming the receiving space may have a substantially rotationally symmetrical shape.

[0057] Furthermore, a tool holder having a chucking device according to the invention is also claimed, the advantages of which are identical to those already recognized for the chucking device according to the invention, and therefore said advantages will not be repeated at this point.

[0058] Preferably, the tool holder may have a coupling device by means of which the tool holder can be releasably coupled to a drive device for rotating the tool holder, in particular to a drive spindle of a machine tool. The coupling device may be formed by a conventional interface for coupling a tool holder to a machine tool, for example by a steep taper interface (ST interface) or a hollow shank taper interface (HST interface).

[0059] Furthermore, a machine tool, in particular a milling machine, having a tool holder according to the invention is also claimed, the advantages of which are identical to those already recognized for the chucking device according to the invention, and therefore these will likewise not be repeated here.

[0060] The description provided above of advantageous refinements of the invention comprises a number of features which are partially combined as a plurality and reproduced in the individual dependent claims. However, these features can also preferably be considered individually and combined to form advantageous further combinations. In particular, these features can be combined in each case individually and in any suitable combination with the method according to the invention.

[0061] In the description and / or claims, if a particular expression is used in each case in the singular or in combination with a numeral, it is not intended that the scope of the invention be limited to the singular or respective numeral for said expression. Furthermore, the words "a" or "an" should be understood as indefinite articles, rather than numerals.

[0062] The above-mentioned characteristics, features, and advantages of the present invention, as well as the manner in which they are realized, will become clearer and more easily understood in conjunction with the following description of exemplary embodiments of the invention, which are described in more detail in conjunction with the drawings / figures (identical components and features have the same reference symbols in the drawings / figures).

[0063] The exemplary embodiments serve to illustrate the invention and do not limit the invention to the combination of features shown therein, nor with respect to functional features. In addition, any feature suitable for this purpose of any exemplary embodiment may be explicitly considered in isolation, removed from one exemplary embodiment, introduced into and supplemented by another exemplary embodiment, or combined with any of the claims. [Brief explanation of the drawings]

[0064] [Figure 1] 1 shows a perspective view of a tool holder having a chucking device according to the present invention; [Figure 2] 2 shows a cross-sectional view taken along the line AA in FIG. 1. [Figure 3] 3 shows a cross-sectional view taken along the section BB in FIG. 2. [Figure 4]1 shows a top view of the base of the tool holder. [Figure 5] FIG. 2 shows a perspective view of a chucking body of the tool holder. [Figure 6] FIG. 1 shows a perspective view of a ring segment element of a tool holder. [Figure 7] FIG. 1 shows a perspective view of a rolling element of a tool holder. [Figure 8] In the illustration according to FIG. 2, a second exemplary embodiment of a tool holder with a chucking device according to the invention is shown. [Figure 9] In the illustration according to FIG. 4, a third exemplary embodiment of a tool holder with a chucking device according to the invention is shown. [Figure 10] 10 shows a top view of the base of a fourth exemplary embodiment of a tool holder with a chucking device according to the present invention; [Figure 11] FIG. 10 shows a perspective view of a bearing cage of a fifth exemplary embodiment of a tool holder with a chucking device according to the present invention; [Figure 12] 6 shows a sixth exemplary embodiment of a tool holder with a chucking device according to the invention in the illustration according to FIG. [Figure 13] 7 shows a seventh exemplary embodiment of a tool holder with a chucking device according to the invention in the illustration according to FIG. [Figure 14] 10 shows a perspective view of a bearing cage of the sixth or seventh exemplary embodiment of a tool holder with a chucking device according to the present invention; FIG. DETAILED DESCRIPTION OF THE INVENTION

[0065] 1 shows a first exemplary embodiment of a tool holder 1 with a chucking device according to the present invention. The tool holder 1 has a base body 3 with a coupling part 5 having a coupling device 4. By means of the coupling device 4, the tool holder 1 can be releasably coupled to a drive spindle of a machine tool (not shown here). Here, the coupling device 4 is formed by a conventional HST interface, for example.

[0066] As further shown in FIG. 2 , the base body 3 also has a receiving part 7, which here is rotationally symmetrical by way of example and has a centrally located receiving space 9. The receiving space 9 here forms an inner cone 10. A collet 11, which is elastic in the radial direction r and has an outer cone 13, is arranged in the receiving space 9. The collet 11 is part of a chucking device 17 of the tool holder 1 and allows a tool, for example a milling tool, to be chucked non-rotatably in the tool holder 1. Here, the collet 11 has a cylindrical tool receiving space 15 in which the tool to be chucked can be positioned by its tool shank.

[0067] 2, the chucking device 17 also has a chucking nut 19 that can be screwed onto the base body 3, and the chucking nut 19 can push the collet 11 into the receiving space 9 in the axial or longitudinal direction x. When the collet 11 is pushed in this way, the collet 11 is compressed in the radial direction r under the action of the conical surface of the inner cone 10 of the base body 3 and the conical surface of the corresponding outer cone 13 of the collet 11. As a result, a tool placed in the tool receiving space 15 can be chucked so that it cannot rotate.

[0068] The chucking nut 19 has a sleeve-type chucking body 21, which is also rotationally symmetrical, for example, and the sleeve-type chucking body 21 allows the chucking nut 19 to be pushed or screwed into the receiving portion 7 of the base body 3. When the chucking nut 19 is pushed in, the sleeve-type chucking body 21 is engaged annularly around the receiving portion 7 with a predetermined gap distance.

[0069] In addition, the chucking nut 19 also has an annular connecting element 22, via which the chucking nut 19 is releasably connected to the collet 11. Here, the annular connecting element 22 is connected to the sleeve-type chucking body 21 of the chucking nut 19 so as to be axially rotatable by a rolling bearing 23. Here, when viewed from the radial direction r, the rolling bearing 23 is in contact on the outer side with an annular web 25 protruding inward of the sleeve-type chucking body 21, and on the inner side with the annular connecting element 22. Here, the rolling body 23 is formed by a cylindrical roller bearing.

[0070] Furthermore, the annular connecting element 22 also has an inwardly protruding annular shoulder 27 having an inner cone, which allows the connecting element 22 to come into flat contact with an end side wall region 29 of the collet 11 when the chucking nut 19 is screwed in, with the wall region forming an outer cone. When the chucking nut 19 is further screwed in, the collet 11 can be pressed into the receiving space 9 of the base 3 by the annular shoulder 27 of the chucking nut 19.

[0071] In addition, the connecting element 22 also has an inwardly protruding web 31 spaced apart in the axial direction x from the annular shoulder 27. In addition, when viewed in the axial direction x, the outwardly protruding web 33 of the collet 11 is disposed between the annular shoulder 27 and the annular web 31. When the chucking nut 19 is unscrewed from the base body 3, the collet 11 is pulled out of the receiving space 9 of the base body 3 by the webs 31, 33.

[0072] In an alternative refinement, the connecting element of the chucking nut and the collet can also be releasably coupled to one another so that, even when the chucking nut is screwed in, the collet can be released from the chucking nut and pulled out of the receiving space in order to change the collet. Such a coupling of a chucking nut and a collet is known, for example, from Patent Document 2, the entire content of which is incorporated by reference into the subject matter of the present application.

[0073] 2 and 3, the chucking nut 19 also has a plurality of, here, four cylindrical rolling elements 35, which are uniformly distributed around the chucking nut 19 in the circumferential direction U. According to FIG. 7, each rolling element 35 has a cylindrical bearing journal 39 protruding from an end side or end wall 37, by which the rolling element 35 is axially rotatably mounted in an annular bearing cage 41 (FIG. 3) of the chucking nut 19. The annular bearing cage 41, together with the rolling elements 32, is contoured and arranged in a recess 42 of the sleeve-type chucking body 21, which extends in the circumferential direction U (FIG. 2) on the inside. The bearing cage 41 is held by an elongated rear engagement web 117 protruding laterally outward in the recess 42 so that the bearing cage 42 can be rotated in the circumferential direction U relative to the sleeve-type chucking body 21.

[0074] Furthermore, the annular bearing cage 41 here is formed in multiple sections with a plurality of, here for example four, ring segment elements 43 ( FIG. 6 ) having a rectangular cross section. By way of example, a single rolling element 35 is assigned to each ring segment element 43. Here, each rolling element 35 is arranged in a continuous recess 115 in the central region 87 of the respective ring segment element 43 so as to conform to its contour when viewed in the circumferential direction U. Additionally, each ring segment element 43 in the central region 87 has a journal receptacle 45, 47 in which the bearing journal 39 of the rolling element 35 is received in accordance with its contour. Here, the journal receptacle 45 of each ring segment element 43 is formed by a hole, and the journal receptacle 47 of each ring segment element 43 is formed by an outwardly open slot. When the chucking nut 19 is installed, the rolling elements 35 are first guided in the holes 45 by one of the bearing journals 39, and then guided in the slots 47 by the other of the bearing journals 41. Furthermore, rear engagement webs 117 that protrude laterally outward are also formed on each ring segment element 43.

[0075] 7, each rolling element 35 also has a predetermined rolling element engagement structure 49. Here, the rolling element engagement structure 49 of each rolling element 35 is formed by a plurality of grooves spaced apart from one another in the rolling element axial direction, and the plurality of grooves form an annular web 51 extending circumferentially around each rolling element 35. In addition, here, the longitudinal axis of the rolling element 35 is arranged parallel to the longitudinal axis of the chucking nut 19. However, alternatively, the longitudinal axis of the rolling element 35 may also be oriented at a predetermined angle of incidence with respect to the longitudinal axis of the chucking nut 19.

[0076] The rolling elements 35 are engaged with a chucking body engagement structure 53 ( FIG. 2 ) of the chucking body 21 by means of a rolling element engagement structure 49 of the rolling element 35, which is formed in a wall region 55 of the chucking body 21 and bounds the recess 42 that it proximally surrounds. The chucking body engagement structure 53 of the chucking body 21 is formed by a plurality of grooves spaced apart from one another in the axial direction x, which form an annular web 57 extending in the circumferential direction U around the chucking body 21. The chucking body engagement structure 53 here forms a guide for the rolling elements 35 in the circumferential direction U.

[0077] Furthermore, the base body 3 of the tool holder 1 also has a plurality of, here four for example, spaced apart engagement regions 61, which are uniformly distributed in the circumferential direction U ( FIG. 4 ) and have base body engagement structures 59 corresponding to the rolling element engagement structures 49. When the chucking nut 19 is screwed in, each rolling element 35 is engaged with the base body engagement structure 59 of the engagement region 61 by the rolling element engagement structure 49 of the rolling element 35. Here, the base body engagement structure 59 of each engagement region 61 is formed by a plurality of spaced apart surrounding grooves, and the plurality of grooves form a web 63 that extends outwardly around the periphery of the base body 3. Here, the base body webs 63 of each engagement region 61 extend parallel to each other.

[0078] Additionally, the grooves in each base-engaging region 61 herein form a base thread. Each base thread 61 herein extends from a start region 65 to an end region 67 when viewed in the circumferential direction U, and the thread pitch of each base thread 61 decreases from the initial region 65 toward the end region 67. Each base thread 61 herein has a first pitch portion 69 having a first constant thread pitch and a second pitch portion 71 having a second constant thread pitch smaller than the first thread pitch. A transition region of continuously or constantly changing thread pitch is provided between the constant thread pitch portions 69, 71.

[0079] The chucking nut 19 can be threaded onto and unscrewed from the base 3 by the rolling element engagement structures 49 of the rolling elements 35 and the base engagement structure 59 of the base 3. When the chucking nut 19 is threaded onto the base 3, the rolling elements 35 first guide the chucking nut 19 into a first pitch portion 69 having a large thread pitch. Here, a relatively large axial distance is covered by the chucking nut 19 over a short threading distance. In this thread region, the chucking nut 19 applies only slight pressure to the collet 11 in the axial direction x. Next, the chucking nut 19 is guided by the rolling elements 35 of the chucking nut 19 into a second pitch portion 71 having a smaller thread pitch. In this thread region, the chucking nut 19 applies a higher or maximum pressure to the collet 11 in the axial direction x.

[0080] Additionally, the chucking nut 19 can be completely removed from the base 3. As a result, for example, the collet 11 can be removed from the chucking nut 19 and replaced with another collet. To remove or install the chucking nut 19, each base engagement region 61 is assigned a receiving notch 83 in the base 3, which extends in the axial direction x and matches the contour of the rolling elements 35. When installing the chucking nut 19 on the base 3, the rolling elements 35 can be introduced into each receiving notch 83 by their circumferential portions until the collet 11 contacts the base 3. Next, starting from each receiving notch 83, the rolling elements 35 can be guided into the base engagement region 61 circumferentially adjacent to the respective receiving notch 83. To remove the chucking nut 19, the chucking nut 19 is placed in a predetermined rotational position relative to the base 3, and at that rotational position, the rolling elements 35 are placed in the receiving notch 83. In this rotation position, the engagement structure between the rolling element 35 and the base body 3 is disengaged, so that the chucking nut 19 can be displaced relative to the base body 3 or removed from the base body 3.

[0081] Furthermore, the tool holder 1 also includes a clamping device for clamping the chucking nut 19 when the chucking nut 19 is screwed into the base body 3. The clamping device is formed on the chucking body 21, and includes a thin-walled clamping web 75 ( FIG. 2 ) that protrudes from a rear end wall 73 of the chucking body 21 and extends annularly in the circumferential direction U. The clamping web 75 allows the chucking nut 19 to come into flat contact with an annular shoulder 76 that protrudes outward from the base body 3 when the chucking nut 19 is screwed into the base body 3. Specifically, the clamping web 75 causes the chucking nut 19 to come into contact with an outer conical wall region 77 that forms the outer cone of the annular shoulder 76. This occurs only when the rolling elements 35 of the chucking nut 19 are located on the second pitch portion 71 of the base body thread 61. When the chucking nut 19 is further screwed in, the clamping web 75 is pressed against the outer conical wall region 77. This achieves a friction-locked fixation of the chucking nut 19.

[0082] Furthermore, the base body 3 also has an end stop that the chucking nut 19 comes into contact with when it is screwed into the base body 3. The end stop may be formed, for example, by an end wall 79 of the base body 3 or by a wall region 81 of the base body 3, which wall region bounds the base engagement region 61 in the circumferential direction.

[0083] FIG. 8 shows a second exemplary embodiment of a tool holder 89 having a chucking device according to the present invention. Compared to the first exemplary embodiment shown in FIGS. 1 to 7, the tool holder 89 here includes a chucking device 91 for chucking a tool instead of the chucking device 17. A tool is chucked in the chucking device 91 without a collet. Instead of a collet, the chucking device 91 here includes a chucking nut 93 having a sleeve-type chucking body 95 and a similar sleeve-type cone 97 connected to the chucking body 95. Here, the bearing cage 41 and the rolling elements 35 held therein are assigned to the chucking body 95. The chucking nut 93 can be pressed or screwed into a receiving portion 98 of the base body 3 by means of the sleeve-type chucking body 95 and the sleeve-type cone 97.

[0084] A tool can be placed by its tool shank in the cylindrical receiving space 85 located in the center of the receiving portion 98. Naturally, the inner diameter of the receiving portion 98 can be adapted to a tool shank having an outer diameter smaller than the inner diameter of the receiving portion 98 by using a cylindrical diameter-reducing bushing.

[0085] The cone body 97 is connected to the chucking body 95 by a rolling bearing 99 so as to be rotatable in the axial direction. When viewed in the radial direction r, the rolling bearing 99 is in contact on the outside with an annular web 101 that protrudes inward of the sleeve-type chucking body 95 and on the inside with an annular web 103 that protrudes outward of the cone body 97. Here, the rolling bearing 99 is formed by a cylindrical roller bearing.

[0086] Furthermore, the conical body 97 connected to the chucking body 95 has an inner conical wall region 105 that forms an inner cone, and the inner conical wall region 105 allows the conical body 97 to come into flat contact with a corresponding outer conical wall region 107 that forms the outer cone of the receiving portion 98 when the chucking nut 93 is screwed into the base body 3. Due to the action of the conical surface, when the chucking nut 93 is further screwed, the receiving portion 98 is pressed inward in the radial direction r against a tool placed in the receiving space 85, thereby chucking the tool so that it cannot rotate.

[0087] FIG. 9 illustrates a third exemplary embodiment of a tool holder with a chucking device according to the present invention. The tool holder includes a base body 109. Compared to the first exemplary embodiment illustrated in FIGS. 1 to 7, the base body 109 now includes a base engagement structure 111 on each engagement region 61. Here, the grooves of each base engagement region 111 also form a base thread having a thread pitch that decreases from the start region 65 toward the end region 67. However, the base thread 111 does not have multiple pitch sections with different constant thread pitches. Instead, the web 112 of each base thread 111 now has a continuously curved profile when viewed in the top view of the base body 109 illustrated in FIG. 9. Here, the radius of curvature of the curved thread 112 continuously increases starting from the start region 65 toward the end region 67 of the base thread 111.

[0088] 10 shows a fourth exemplary embodiment of a tool holder having a clamping device according to the present invention. This tool holder has a base 119. Compared to the first exemplary embodiment shown in FIGS. 1 to 7, the base 109 here does not have multiple engagement regions each having a base engagement structure. Instead, the base 119 has a single base engagement structure 121 that can engage the rolling elements 35 of the chucking nut 19. The chucking nut 19 can be threaded onto and unscrewed from the base 119 by the mutually engaged engagement structures 49, 121 of the base 119 and the rolling elements 35.

[0089] Here, the base engaging structure 121 is formed, for example, by a thread having a plurality of surrounding grooves, and the threads form a plurality of, here, for example, four webs 131 that extend spirally around the outside of the periphery of the base 119. Thus, here, the base engaging structure 121 is in the form of a conventional four-lead thread. Alternatively, the thread may be formed by a single-start thread.

[0090] FIG. 11 shows a fifth exemplary embodiment of a tool holder with a chucking device according to the present invention. The tool holder has a bearing cage 123. Compared to the first exemplary embodiment shown in FIGS. 1 to 7, the bearing cage 123 is formed by two annular receiving elements 125, 127. Each receiving element has four consecutive holes 129 corresponding to the number of rolling elements 35 as journal receptacles, in which the rolling elements 35 can be positioned by their bearing journals 39 in a manner that adapts to their contours. Then, when the tool holder is mounted, each rolling element 35 is positioned in the hole 129 of the annular receiving element 125 by the bearing journal 39, and in the hole 129 of the receiving element 127 by the other axially opposite bearing journal 39.

[0091] FIG. 12 shows a sixth exemplary embodiment of a tool holder 1 with a chucking device according to the invention.

[0092] The "sixth" tool holder 1 is designed similarly to the tool holder according to the first or fourth exemplary embodiment, and therefore components not mentioned or specifically mentioned below correspond to components of the first or fourth exemplary embodiment.

[0093] 12, the tool holder 1 has a base 119 with a coupling portion 5 having a coupling device 4. The tool holder 1 can be releasably coupled to a drive spindle of a machine tool (not shown) by means of the coupling device 4. Here, the coupling device 4 is formed, by way of example, by a conventional HST interface.

[0094] As further shown in FIG. 12 , the base body 119 also has a receiving part 7, which here is rotationally symmetrical by way of example and has a centrally located receiving space 9. The receiving space 9 here forms an inner cone 10. A resilient collet 11 having a slot (145) in the radial direction r and an outer cone 13 is arranged in the receiving space 9. The collet 11 is part of a chucking device 17 of the tool holder 1, which chucking device allows a tool, for example a milling tool, to be chucked non-rotatably in the tool holder 1. Here, the collet 11 has a cylindrical tool receiving space 15 in which the tool to be chucked can be positioned by its tool shank.

[0095] 12, the chucking device 17 also has a chucking nut 19 that can be screwed onto the base body 119, and the chucking nut 19 can push the collet 11 into the receiving space 9 in the axial or longitudinal direction x. When the collet 11 is pushed in this way, the collet 11 is compressed in the radial direction r under the action of the conical surface of the inner cone 10 of the base body 119 and the conical surface of the corresponding outer cone 13 of the collet 11. As a result, a tool placed in the tool receiving space 15 can be chucked so that it cannot rotate.

[0096] The chucking nut 19 has a sleeve-type chucking body 21, which is again rotationally symmetrical by way of example, and this allows the chucking nut 19 to be pushed or screwed into the receiving portion 7 of the base body 3. When the chucking nut 19 is pushed in, the sleeve-type chucking body 21 annularly engages with the periphery of the receiving portion 7 with a predetermined gap distance.

[0097] In addition, the chucking nut 19 also has an annular connecting element 22, through which the chucking nut 19 is releasably connected to the collet 11. Here, the annular connecting element 22 is connected to the sleeve-type chucking body 21 of the chucking nut 19 by a rolling bearing 23 so as to be axially rotatable. Here, the rolling bearing 23 is formed by a cylindrical roller bearing.

[0098] The connecting element 22 of the chucking nut 19 and the collet 11 are coupled to one another via a bayonet lock 137, the collet 11 providing longitudinal and transverse slots or notches 151 and the connecting element 22 having corresponding protrusions 153.

[0099] According to Figure 12 (and Figure 14), the chucking device has a plurality of cylindrical rolling elements 35, here 20 for example, which are held uniformly distributed in the circumferential direction U by window-type cages 41 (the number of corresponding pockets 131 (here, for example 20)) and are disposed between the chucking nut 19 and the base body 119 (see Figure 14 in particular).

[0100] 12 (and 14), each rolling element 35 has a predetermined rolling element engagement structure 49. Here, the rolling element engagement structure 49 of each rolling element 35 is formed by a plurality of grooves spaced apart from one another in the rolling element axial direction (by a particular groove width 155), and the plurality of grooves form an annular web 51 extending circumferentially around each rolling element 35. In addition, here, the longitudinal axis of the rolling element 35 is arranged parallel to the longitudinal axis of the chucking nut 19.

[0101] The rolling body 35 is engaged with the chucking body engagement structure 53 (FIG. 12) of the chucking body 21 by the rolling body engagement structure 49 of the rolling body 35, which here has the form of a single-start (internal) thread, the pitch of which matches a groove width 155 having a pitch of, for example, 5 mm (=groove width 155) formed on the inner peripheral surface or inner wall region of the chucking body 21.

[0102] Furthermore, the base 119 of the tool holder 1 has a base engagement structure 121 on its outer peripheral surface or outer wall region that corresponds to the chucking body engagement structure 53 (FIG. 12) of the chucking body 21 or the rolling body engagement structure 49 of the rolling body 35, and therefore also has a single-start (external) thread (with a pitch of 5 mm).

[0103] When the chucking nut 19 is screwed in, each rolling element 35 is engaged with the base engagement structure 121 of the base 119 and the chucking element engagement structure 53 of the chucking element 21 (FIG. 12) by the rolling element engagement structure 49 of the rolling element 35.

[0104] The rolling element engagement structure 49 of the rolling element 35 and the base engagement structure 121 of the base 119 allow the rolling element and the base to be screwed together (screwed in / unscrewed), and the rolling element engagement structure 49 of the rolling element 35 and the chucking body engagement structure 53 of the chucking body 21 allow the rolling element and the chucking body to be screwed together, and the chucking nut 19 can be screwed into the base 119 or unscrewed from the base 119.

[0105] 12, the chucking device provides anti-twist means 139 between the collet 11 and the base 119. The anti-twist means in this case is formed by an axial extension 141 on the collet 11 and a complementary engagement point 143 on the base 119.

[0106] A cover ring 157, which is screwed onto the chucking nut 19 or the chucking body 21 of the chucking nut 19 at one end, is used to cover or shield the gap between the chucking nut 19 or the chucking body 21 of the chucking nut 19 and the base body 119 (into which the rolling elements 35 housed in the window-type cage 41 are inserted). Here, the depth to which the cover ring 157 is screwed into the chucking body 21 is defined by a shoulder 159 of the chucking body 21, and the shoulder also simultaneously constitutes the start portion at one end of the chucking body engagement structure 53 (FIG. 12) of the chucking body 21.

[0107] As described in the first exemplary embodiment (see FIG. 2 ), although not shown, the tool holder 1 here may optionally have a clamping device for clamping the chucking nut 19 when the chucking nut 19 is threaded into the base 3, and may also have a base end stop that the chucking nut 19 contacts when the chucking nut 19 is threaded into the base 3.

[0108] FIG. 13 shows a seventh exemplary embodiment of a tool holder 89 having a chucking device according to the present invention.

[0109] The "seventh" tool holder 1 is formed similarly to the tool holder of the second or fourth exemplary embodiment, and therefore components not described or specifically described below correspond to components of the first or fourth exemplary embodiment.

[0110] 12, the tool holder 89 here includes a chucking device 91 for chucking a tool, instead of the chucking device 17. The tool is chucked in the chucking device 91 without a collet.

[0111] Instead, the chucking device 91 here has a chucking nut 93 having a sleeve-type chucking body 95 and a similar sleeve-type cone 97 connected to the chucking body 95 (via the connecting element 22).

[0112] As shown in FIG. 13 , the cone 97 connected to the chucking body 95 has an inner conical wall region 105 that forms an inner cone that allows the cone 97 to come into flat contact with a corresponding outer conical wall region 107 that forms the outer cone of the receiving portion 98 when the chucking nut 93 is screwed into the base body 119. When the chucking nut 93 is further screwed under the action of the conical surfaces 105 / 107, the receiving portion 98 is pressed inward in the radial direction r against a tool placed in the receiving space 85, thereby chucking the tool so that it cannot rotate.

[0113] It should also be appreciated that the inner diameter of the receiving portion 98 may be adapted to a tool shank having an outer diameter smaller than the inner diameter of the receiving portion 98 using a cylindrical diameter reducing bushing.

[0114] Again, in this clamping device, the bearing cage 41 and rolling elements 35 (see FIG. 14) held therein and having the rolling element engagement structure 49 are disposed between the chucking body 95 and the base body 119 .

[0115] The rolling bodies 35, for example 20 in number here, are again engaged with the chucking body engagement structures 53 of the chucking body 95 by the rolling body engagement structures 49 of the rolling bodies 35, said chucking body engagement structures being formed on the inner peripheral surface or inner wall region of the chucking body 95.

[0116] Furthermore, the base 119 again has, on its outer circumferential surface or outer wall region, a base engagement structure 121 that corresponds to the chucking body engagement structure 53 of the chucking body 95 or the rolling element engagement structure 49 of the rolling element 35. The rolling element 35 is also engaged with said base engagement structure 121 by the rolling element engagement structure 49 of the rolling element 35.

[0117] The chucking body engagement structure 53 and the base body engagement structure 121 are again each a single-start thread, with an exemplary pitch of 5 mm, and the rolling body engagement structure 49 is again formed by grooves (from the web 51) spaced apart corresponding to the pitch.

[0118] When the chucking nut 19 is screwed in, each rolling element 35 is engaged with the base engagement structure 121 of the base 119 and the chucking element engagement structure 53 of the chucking element 95 (FIG. 12) by the rolling element engagement structure 49 of the rolling element 35.

[0119] The rolling element engagement structure 49 of the rolling element 35 and the base engagement structure 121 of the base 119 allow the rolling element and the base to be screwed together (screwed in / unscrewed), the rolling element engagement structure 49 of the rolling element 35 and the chucking body engagement structure 53 of the chucking body 95 allow the rolling element and the chucking body to be screwed together, and the chucking nut 93 can be pushed, screwed in or unscrewed into the receiving portion 98 of the base 119 by the sleeve-type chucking body 95 and the sleeve-type cone 97.

[0120] In addition, the chucking nut 93 again has an annular connecting element 22, via which the chucking nut 93 is releasably connected to the sleeve-type cone body 97. The annular connecting element 22 is again axially rotatably connected to the sleeve-type chucking body 95 of the chucking nut 93 by a rolling bearing 23. Here again, the rolling bearing 23 is formed by a cylindrical roller bearing.

[0121] In this exemplary embodiment, the connecting element 22 of the chucking nut 93 and the sleeve-type cone 97 are again coupled to one another via a bayonet lock 137, with the sleeve-type cone 97 providing longitudinal and transverse slots or notches 141 and the connecting element 22 having corresponding protrusions 143.

[0122] A cover ring 157, which is screwed onto the chucking nut 93 or the chucking body 95 of the chucking nut 93 at one end, is used to cover or shield the gap between the chucking nut 93 or the chucking body 95 of the chucking nut 93 and the base body 119 (into which the rolling elements 35 housed in the window-type cage 41 are introduced). Here, the depth to which the cover ring 157 is screwed into the chucking body 95 is determined by a shoulder 159 of the chucking body 95, and the shoulder also constitutes a start portion at one end of the chucking body engagement structure 53 (FIG. 12) of the chucking body 95.

[0123] Figure 14 shows the rolling element 35 (and the rolling element engagement structure 49 of the rolling element 35) and the window-type cage 41 of the rolling element 35, as provided in the sixth and seventh exemplary embodiments described above (according to Figures 12 and 13).

[0124] As shown in Figure 14, here, for example, 20 cylindrical rolling elements 35 are uniformly distributed in the circumferential direction U, spaced apart by the webs 149 of the window-type cage 41, and held in the window-type cage 41 (with a corresponding number of 20 identical pockets 133 uniformly distributed in the circumferential direction).

[0125] Here, the axial length of the pocket 133 of the window-type cage 41 substantially corresponds to the axial length of the rolling element 35, and the width of the pocket is greater than the width of the rolling element with a slight play, so that the rolling element 35 can be accommodated / held with a play in the pocket 133. The web side facing the pocket 133 is curved concavely (not shown) to correspond to the rolling element 35.

[0126] 14, each adjacent pocket 133 around the circumferential direction U has an axial offset 135, which is adapted to the thread pitch of the base engagement structure 121 or the thread pitch of the chucking body engagement structure 53 and the number of rolling elements. That is, in this example, the thread pitch is 5 mm and the number of rolling elements is 20, so the axial offset 135 is 0.25 mm (5 mm / 20). As a result, a precise pitch (overall) offset 147 is formed between the last pocket and the first pocket around the window-type cage 41.

[0127] It should be noted that in the window-type cage 41, instead of such a stepped offset 135 between the pockets 133 which are each slightly offset axially, the pockets may be slightly tilted to allow for a continuous offset, which may allow the rolling elements to be slightly tilted and make screwing easier. [Explanation of symbols]

[0128] 1 Tool holder 3 Base 4 Coupling device 5 Connecting part 7 Receiving section 9 Reception space 10 Inner Cone 11 Colette 13 Outer Cone 15 Tool receiving space 17 Chucking device 19 Chucking nut 21 Chucking body 22 Connecting Elements 23 Rolling bearings 25 Web 27 Shoulder 29 Wall area 31 Web 33 Web 35 rolling elements 37 End Wall 39 Bearing journal 41 Bearing cage 42 Depression 43 Ring Segment Elements 45 Journal Receptacle 47 Journal Receptacle 49 Rolling element engagement structure 51 Web 53 Chucking body engagement structure 55 Wall area 57 Web 59 Base engagement structure 61 Engagement area 63 Web 65 Start area 67 End area 69 Pitch part 71 Pitch section 73 End Wall 75 Breaking Web 76 Shoulder 77 Outer Cone Wall Area 79 End Wall 81 Wall area 83 Receiving groove 85 Reception Space 87 Central area 89 Tool holder 91 Chucking device 93 Chucking Nut 95 Chucking body 97 Cone 98 Receiving Section 99 Rolling bearings 101 Web 103 Web 105 Inner cone wall area 107 Outer Cone Wall Area 109 Substrate 111 Base engagement structure 112 Web 115 Depression 117 rear engagement web 119 Base 121 Base engagement structure 123 Bearing cage 125 Acceptance Elements 127 Acceptance Elements 129 holes 131 Web 133 Pocket 135 axial offset 137 Locking devices, bayonet locks 139 Twist prevention measures 141 Extension 143 Engagement part 145 slots 147 total offsets 149 Web 151 (longitudinal / transverse) notches / slots 153 Protrusion 155 groove width 157 Covering 159 Shoulder

Claims

1. A chucking tool for chucking a tool, which is an object, comprising a base body (3; 109; 119) having a receiving space (9; 100) in which the tool, which is an object, can be placed, wherein the chucking device (17; 91) comprises a plurality of cylindrical rolling elements (35) having a predetermined rolling element engagement structure (49) and a chucking nut (19; 93) that can be screwed onto the base body (3; 109; 119), and the object placed in the receiving space (9; 100) can be chucked so as not to rotate when the chucking nut is screwed onto the base body (3; 109; 119); The rolling elements (35) are held rotatably around the axis of the rolling elements (35) in a sleeve-type chucking element (21; 95) of the chucking nut (19; 93), and are distributed around the chucking nut (19; 93) in the circumferential direction (U); or In the chucking device (17; 91), the chucking nuts (19; 93) are arranged rotatably around the axis and are distributed in the circumferential direction (U) between the sleeve-type chucking body (21; 95) and the base body (3; 109; 119); at least one base engagement structure (59; 111; 121) is formed on the base (3; 109; 119), and the rolling elements (35) are engaged or can be engaged with the at least one base engagement structure (59; 111; 121) of the base (3; 109; 119) by rolling element engagement structures (49) of the rolling elements (35); the chucking nut (19; 93) can be screwed into or unscrewed from the base body (3; 109; 119) by the engagement structures (49, 59; 111; 121) engaging with each other and by the rolling elements (35) rolling on the base body (3; 109; 119).

2. 2. The chucking device of claim 1, wherein the base-engaging structure (121) is formed by a thread having at least one groove, the groove forming at least one web (131) that extends spirally outwardly around the base (119), and the thread having multiple leads.

3. A plurality of engagement regions (61) distributed in the circumferential direction (U) and spaced apart from one another and having base body engagement structures (59; 111) are formed on the base body (3; 109) of the chucking device (1), and the rolling elements (35) are engaged or can be engaged with the base body engagement structures (59; 111) of the base body (3; 109) by the engagement structures (49) of the rolling elements (35); 2. The chucking device according to claim 1, wherein the chucking nut (19; 93) can be screwed into and unscrewed from the base body (3; 109) by the engagement structures (49, 59; 111) of the rolling element (35) and the base body (3; 109) which are engaged with each other and by the rolling element (35) rolling on the base body (3; 109).

4. 4. The chucking device according to claim 1, wherein the rolling element engagement structure (49) of each rolling element (35) is formed by a plurality of grooves spaced apart from one another in the axial direction of the rolling element (35), and by an annular web (51) extending in the circumferential direction around each rolling element (35), and the side surfaces of the annular web (51) are curved.

5. 5. The chucking device according to claim 1, wherein each of the rolling elements has a bearing journal protruding from an end side, and each of the rolling elements is held by the bearing journal so as to be rotatable about the axis in the chucking body of the chucking nut, or each of the rolling elements is attached by the bearing journal to an annular, circular bearing cage of the chucking nut so as to be rotatable about the axis, the bearing cage being formed from a plurality of portions having a plurality of ring segment elements having a rectangular cross section in the axial direction of the annular, circular bearing cage, and at least one of the rolling elements is assigned to at least one of the ring segment elements.

6. the rolling elements (35) are accommodated in a window-type cage (41) which is a bearing cage (41; 123) and has pockets (133) for the rolling elements (35), the rolling elements (35) being accommodated with a large axial play in the pockets (133) of the window-type cage (41), or the axial length of the pocket (133) of the window-type cage (41) corresponds to the axial length of the rolling element (35); a selected pocket (133) of the window-type cage (41) has an axial offset (135) relative to other pockets (133) of the window-type cage (41), and the axial offset (135) of the pocket (41) is determined so that the total length of the axial offset (135) is equal to the length of the thread pitch of the base body engagement structure (121) and / or the thread pitch of the chucking body engagement structure (53) of the chucking body (21, 95), by which the chucking body engagement structure (53) of the chucking body (21, 95) engages with the rolling body engagement structure (49) of the rolling body (35); and / or 6. The chucking device according to claim 1, wherein the axial offset (135) is a length obtained by dividing the thread pitch of the base body engagement structure (121) or the thread pitch of the chucking body engagement structure (53) of the chucking body (21, 95) by the number of the rolling bodies (35).

7. 6. The chucking device according to claim 1, wherein the chucking body (21, 95) has a chucking body engagement structure (53) by which the chucking body (21, 95) engages with the rolling body engagement structure (49) of the rolling body (35), the chucking body engagement structure (53) being formed by a plurality of grooves arranged at intervals, the plurality of grooves forming an annular web (57) extending inward in the circumferential direction (U) of the chucking body (21), or the chucking body engagement structure (53) being formed by a thread having at least one screw groove, the screw groove forming at least one web (131) extending helically inward in the circumferential direction (U) of the chucking body (21, 95), the thread having a plurality of leads, the number of leads of the thread corresponding to the number of the rolling bodies (35).

8. 8. The chucking tool according to claim 6 or 7, characterized in that the chucking body (21) has an inner recess (42) extending in the circumferential direction (U), a bearing cage (41; 123) is arranged in the recess (42) so as to match its contour, and a wall region (55) of the chucking body (21) that bounds the recess (42) on its base side forms the chucking body engagement structure (53) of the chucking body (21), and / or the chucking body engagement structure (53) is arranged in the wall region (55) of the chucking body (21) that surrounds it in the circumferential direction (U).

9. The chucking device (17) comprises a collet (11) arranged in the receiving space (9) and elastic in the radial direction (r) and having an outer cone, the collet (11) being pressable into the receiving space (9) of the base body (3; 109; 119) by the chucking nut (19), the receiving space forming an inner cone, so that an object placed in the cylindrical object receiving space (15) of the collet (11) can be chucked non-rotatably, and an annular connecting element (22) is provided, the annular connecting element (22) being 9. The chucking device according to claim 1, wherein the chucking nut (19) is releasably connected to the collet (11) via an annular connecting element (22), the annular connecting element (22) is connected to the chucking body (21) of the chucking nut (19) by a rolling bearing (23) so as to be rotatable about the axis, and / or the annular connecting element (22) is or can be locked to the collet (11) by a bayonet lock that is a locking device (137).

10. 10. The chucking device according to claim 1, wherein the chucking nut (93) has a sleeve-type conical body (97) connected to the chucking body (95) and an inner conical wall region (105) forming an inner cone, and when the chucking nut (93) is screwed onto the base body (3, 119), the conical body (97) comes into flat contact with a receiving portion (98) of the base body by means of the inner conical wall region (105), and the receiving portion forms the receiving space (100), pressing the receiving portion (98) inward against an object placed in the cylindrical receiving space (100), thereby chucking the object so that it cannot rotate.

11. 11. The chucking device according to claim 1, wherein the base body (3) has an end stop against which the chucking nut (19) comes into contact when screwed onto the base body (3), the end stop being formed by or oriented towards the end of at least one wall region (79) of the base body, or by at least one wall region (81) of the base body (3), the wall region bounding a base body engagement region (61) in the circumferential direction (U).

12. 12. The chucking device according to claim 1, further comprising a clamping device for clamping the chucking nut (19; 93) when the chucking nut (19; 93) is screwed onto the base body (3; 109; 119), the clamping device comprising an annular, thin-walled clamping web (75) formed on the chucking body (21; 95), the clamping web (75) protruding from an end wall (73) of the chucking body (21; 95), the chucking nut (19; 93) coming into planar contact with a corresponding contact wall area by the clamping web (75) when screwed onto the base body (3; 109; 119).

13. A tool holder for a milling machine, which is a machine tool, comprising a chucking device according to any one of claims 1 to 12.

14. 14. The tool holder according to claim 13, characterized in that the tool holder (1) has a coupling device (4) by means of which the tool holder (1) can be coupled to a drive spindle of a machine tool, which is a drive device for driving the tool holder in rotation.

15. A milling machine comprising a tool holder (1) according to claim 13 or 14.

Images