The invention relates to a device for coupling two components, in particular two tool parts, having a locating pin which is arranged on the first component and has a substantially cylindrical lateral surface, and having a radially projecting annular planar face which delimits the locating pin at its root, having a receiving sleeve which is arranged on the second component and has a cylindrical inner face and is delimited by an annular end face, and having a clamping mechanism which pulls the locating pin into the receiving sleeve and, here, presses the planar face and the end face against one another, with the receiving sleeve having an inner cone part which diverges from the cylindrical inner face toward the end face, and with the locating pin supporting an outer cone part which is complementary thereto.
The coupling device according to the invention is designed primarily for detachably coupling tools to a machine spindle (interface) and for connecting tool parts to one another (parting point). “Tool parts” are to be understood in particular to mean bore rods, elongation and reduction pieces, adjusting heads, spindle ancillary flanges and machine spindles.
In known couplings of said type, the centering takes place by means of the cylinder fit of the locating pin in the receiving sleeve, while the rotary drive takes place predominantly by means of friction on account of the planar face clamping between the planar face and the end face. In cylinder fits, there is in principle always a certain radial play between the locating pin and receiving sleeve. In order to avoid said disadvantage, it has already been proposed (DE 102 33 694 A1) that the locating pin has, in the region of its root, an outer cone part which diverges from the cylindrical lateral surface to the planar face and which is integrally formed on the locating pin. In order to ensure sufficient planar face clamping for the rotary drive, it is proposed there above all that the inner cone part can be elastically expanded under the action of the clamping mechanism. For this purpose, a material weakening is required in the region of the end part of the sleeve, which is perceived to be disadvantageous.
The invention is based on the object of improving the known coupling device of the type specified in the introduction in such a way that good centering properties and sufficient planar face clamping for the rotary drive are ensured even without a material weakening in the sleeve region.
To achieve said object, the combinations of features specified in patent claims 1 and 26 are proposed. Advantageous embodiments and refinements of the invention can be gathered from the dependent claims.
The solution according to the invention consists primarily in that the locating pin supports, in its root region, an elastically deformable centering ring which has the outer cone part. The centering ring is expediently plugged onto the locating pin. In order to ensure precise positioning of the centering ring on the locating pin, the centering ring should be connected to the locating pin in a form-fitting and/or force-fitting manner. For this purpose, the locating pin can have an encircling open-edged recess for receiving the centering ring. If the centering ring is detachable from the locating pin, it can, in order to create compatibility with conventional clutch systems of said type, be removed from the locating pin. It is however fundamentally also possible for the centering ring to be shrunk onto the locating pin.
According to one preferred embodiment of the invention, the open-edged recess extends into an axial undercut in the planar face of the first component. Here, the open-edged recess has an oversize with respect to the centering ring, which permits the elastic deformation of the latter during the joining process. The centering ring is expediently composed of resiliently elastic material, preferably of spring steel.
A further preferred embodiment of the invention provides that the centering ring has an annular base part which is connected to the locating pin in a form-fitting, force-fitting and/or cohesive fashion, and an annular spring part which axially adjoins the base part, projects freely beyond the adjacent lateral surface of the locating pin and supports the outer cone part. Here, the centering ring can, with its base part, be latched, shrunk, adhesively bonded, welded and/or soldered onto the locating pin. The spring part is integrally formed either on that side of the base part which faces toward the locating pin root or on that side of the base part which faces away from the locating pin root. Accordingly, the spring part projects beyond the base part, which is fixed to the locating pin, either in the direction of the locating pin root or in the opposite direction.
Here, it is expediently proposed that the centering ring has an annular base part which bears against a cylindrical section of the locating pin, and a spring part which projects axially beyond the base part and engages into the open-edged recess. Accordingly, the locating pin has a cylindrical centering section which is arranged at an axial distance from the planar face, which cylindrical centering section is adjoined in the direction of the planar face, via a delimiting step, by the open-edged recess with smaller diameter than the centering section. Here, the centering ring is, with its base part, expediently plugged or shrunk onto the cylindrical section of the locating pin with fitting accuracy. For this purpose, the base part of the centering ring has a centering opening which is matched in diameter to the centering section of the locating pin and whose inner diameter is smaller than the diameter in the region of the spring part. Here, the inner diameter in the region of the spring part can vary over the axial extent of the centering ring. The undercut advantageously has a run-on bevel, which points obliquely in the direction of the component axis, for the spring part of the centering ring. During the joining process, the spring part migrates along the run-on bevel in the direction of the component axis. For this purpose, the centering ring has, in the region of the spring part, an annular bending zone formed by a material thinning. It is particularly advantageous in this context if the cone angle of the sleeve-side inner cone is, when the locating pin is loose, steeper than the cone angle of the centering-ring-side outer cone. In this case, during the joining process, the receiving sleeve abuts with the end edge of its inner cone firstly against the outer cone of the centering ring, so that the spring part can bend inward along the run-on bevel and the cone angle of the centering ring is gradually aligned with the cone angle of the outer cone. When the locating pin is clamped, there is finally areal contact between the inner cone of the receiving sleeve and the outer cone of the centering ring. A peculiarity of the construction according to the invention is that the centering, in the clamped state, is placed in contact at three points arranged at a distance from one another to form annular contact, specifically, in the region of the base part, at the inside against the centering section of the locating pin, in the region of the spring part, at the outside against the inner cone of the receiving sleeve, and in the region of the locating pin root, at the end side against an undercut face.
A further advantageous embodiment of the invention provides that a sealing ring, composed of elastomeric material, is enclosed between the locating pin and the centering ring, which sealing ring prevents the infiltration of dirt into the intermediate region. Here, the sealing ring can be integrally vulcanized either on the locating pin or on the centering ring.
In order to facilitate assembly of the centering ring, the latter can have a plurality of spreading slots which are arranged so as to be distributed over the periphery and are open axially toward the base part side and/or toward the spring part side. During the clamping process, the spreading slots ensure that the elimination of play at the contact points between the components with the interposition of the spreading ring is facilitated.
The cone angle of the inner and of the outer cone is expediently dimensioned such that no self-locking occurs. Said cone angle should therefore be at least 8°.
According to a further preferred or alternative embodiment variant in which the receiving sleeve and/or the locating pin have a cone part which diverges from its cylindrical lateral surface or inner face toward the end or planar face, which cone part is embodied as an inner cone part in the case of the receiving sleeve and as an outer cone part in the case of the locating pin, it is proposed according to the invention that an annularly encircling pocket which is formed into the receiving sleeve and/or into the locating pin is provided between the receiving sleeve and the locating pin in the region of the at least one cone part, in which pocket is arranged a cage ring which is composed of elastically deformable material and which is fitted with support bodies, preferably embodied as support balls, which are arranged so as to be distributed in the peripheral direction and which, in the joined state, are supported against the delimiting walls, which face towards one another in the region of the pocket, of the receiving sleeve and of the locating pin. Here, the cage ring is expediently composed of a polymer material which performs both a retaining function for the support balls and also a sealing function.
In order to facilitate the joining process, the cage ring is expediently connected in a form-fitting and/or force-fitting manner to one of the two components. For this purpose, the cage ring can be latched, clamped or screwed onto one of the two components. One preferred embodiment of the invention provides that the encircling pocket is formed into the receiving sleeve and the cage ring is fixed in said pocket. In this way, a situation is obtained in which retrofitting is necessary only on the side of the receiving sleeve.
Additionally, the measures according to the invention allow trisection to be generated over the length of the locating pin and of the receiving sleeve: the clamping mechanism is situated in the cylindrical part of the locating pin and of the receiving sleeve. The conical parts in the region of the centering ring and of the receiving sleeve ensure the centering. The planar face clamping which takes place under the action of the clamping mechanism effects the rotary drive. The asymmetry in the planar face clamping introduced by the clamping mechanism is compensated by the elastically compressible centering ring. With suitable dimensioning of the locating pin fit in the locating bore, during the clamping process, there is additionally contact between the bore wall and the locating pin and therefore an increase in the bending stiffness in the connecting region.
According to one preferred embodiment of the invention, the clamping mechanism has a clamping bolt which is movably arranged in a transverse bore of the locating pin and which has, at its ends, an inner or outer cone, and two clamping elements which are situated diametrically oppositely with respect to the cylindrical inner face of the receiving sleeve, which, during the clamping process, can be clamped in a wedged fashion to the clamping bolt under bending of the centering ring and under mutual pressing of the components in the region of the planar face, and which are preferably embodied as holding screws. In this way, a situation is obtained in which the planar face clamping is generated by the clamping bolts and the clamping bolts and the clamping elements, while the centering and stiffening of the coupling takes place by means of the cone parts on the centering ring and in the receiving sleeve. Tests have shown that the reproducibility in the joining process is significantly improved on account of the conical elimination of play by means of the centering in relation to the variant with an outer cone integrally formed on the locating pin. With the measures according to the invention, it is also possible for the rotationally symmetrical coupling faces of the first and second components in each case to be hard-turned and if appropriate ground in a precisely concentric fashion in a clamped machine support. This ensures a high degree of centering accuracy.
The above advantages can also be obtained when using a clamping mechanism which has a tension bolt which projects axially beyond the end-side end of the locating pin, and also a pull-in device which is arranged at the machine side and which engages axially on the tension bolt through a passage opening in the receiving sleeve.
The invention is explained in more detail below on the basis of the exemplary embodiments schematically illustrated in the drawing, in which:
a shows a detail of a first embodiment variant of the coupling point between the two tool parts as per
b shows an enlarged detail from
a shows a detail of a second embodiment variant of the coupling point between the two tool parts as per
b shows an enlarged detail from
a shows a detail of a third embodiment variant of the coupling point between the two tool parts as per
b shows an enlarged detail from
a to c show three embodiment variants of the workpiece fitted with the locating pin, with three differently-designed centering rings, in a diagrammatic illustration;
a and b to
a and b show some further embodiment variants of the coupling point between the two tool parts in section illustrations corresponding to
The connecting devices illustrated in the drawing serve for detachably connecting components 10, 12. Below, “components” are to be understood to mean primarily tool parts which contain either a locating pin 14 or a receiving sleeve 16. In the exemplary embodiment shown in
The connecting device is composed substantially of a locating pin 14 which projects axially beyond the first component 10, a receiving sleeve 16 which is arranged on the second component, and a clamping mechanism 20 for pulling the locating pin 14 into the receiving sleeve 16 and for generating planar face clamping between the annular planar face 22, which delimits the locating pin 14, of the first component 10, and the end face 24, which delimits the receiving sleeve 16, of the second component 12. The locating pin 14 has a substantially cylindrical lateral surface 26 onto which is plugged, in the region of its root 28, a centering ring 29 with an outer cone part 30 which diverges toward the planar face 22. At the other side, the receiving sleeve of the second component 12 has a substantially cylindrical inner face 32 which is embodied as a locating bore and which merges into an inner cone part 34 which diverges toward the end face 24.
A peculiarity of the invention is that the centering ring 29 which is arranged in the root region of the locating pin 14 is elastically deformable, that is to say is composed of an elastically bendable material, preferably of spring steel. Said centering ring 29 is plugged onto the locating pin and is connected to the latter in a form-fitting and/or force-fitting manner. For this purpose, the locating pin 14 has an encircling open-edged recess 36 for receiving the centering ring 29, which recess 36 extends into an axial undercut 37 in the annular planar face 22 of the first component 10. The open-edged recess 36 has an oversize with respect to the centering ring ˜29 which permits the elastic deformation of the latter.
As indicated in
The exemplary embodiments as per
In the embodiment variant as per
The embodiment variant shown in
In order to improve the bendability of the centering ring 29, it is possible to provide spreading or bending slots 76, 78 which are arranged so as to be distributed over the periphery and are open either axially toward the base part edge and/or toward the spring part edge (cf.
The embodiment variants, shown in
In the embodiment variants as per
In the case of
In order to obtain a clear assignment between the centering ring 29 and component, in the case of
In the exemplary embodiment as per
In the exemplary embodiment as per
In the exemplary embodiment as per
The clamping mechanism 20 as per
In order to produce a connection between the two components 10, 12, firstly the locating pin 14 is inserted, when the movement screw 54 is unscrewed, loose into the receiving sleeve 16 of the second component 12. As the movement screw 54 is subsequently screwed into the internal thread 50, there is firstly abutment between the movement screw 54 and the clamping bolt 46 in the region of the conical faces 82, 84 which face toward one another. During the further course of the clamping process, the clamping bolt 46 is inserted with its outer cone 78 into the inner cone 80 until it abuts against the stop screw 52. In this state, the actual clamping process begins, in which the clamping forces introduced by the holding screws 52, 54 are converted, via the conical contact faces 78, 80, 82, 84 of the clamping mechanism 20, axial forces which pull the locating pin 14 into the receiving sleeve 16. The axial forces lead firstly to bending of the spring part 60 of the centering ring 29 by means of the inner cone part 34 of the receiving sleeve 16 until the end face 24 of the receiving sleeve 16 bears against the planar face 22 of the locating pin 14. As the movement screw 54 is further tightened, there is finally planar face clamping between the end face 24 and the planar face 22. The outer and inner cone parts 30, 34, which bear against one another, of the centering ring 29 and of the receiving sleeve 16 ensure precise centering of the components 10, 12 and eliminate the play present in the region of the cylinder fit and the asymmetry present in the clamping mechanism 20.
In the exemplary embodiments shown, a sealing ring 98 which is provided with an axial aperture 96 is situated between the end side of the locating pin 14 and the base of the receiving sleeve 16, which sealing ring 98 seals off a coolant duct 100, which is conducted through the coupling device, to the outside. The coolant duct 100 which passes from the second component opens out through the sealing ring 98 into a coolant tube 102 which is inserted, without a step, through the clamping mechanism 20.
The clamping mechanism 20 plays only a secondary role in the invention. For example, it is also possible, as per
In summary, the following is to be noted: the invention relates two a device for coupling two components 10, 12, for example to tool parts. The first component 10 has a cylindrical locating pin 14 and a radially projecting planar face 22 which delimits the locating pin at its root 28, while the second component 12 has a receiving sleeve 16 with a cylindrical inner face 32. Also provided is a clamping mechanism 20 which, during the clamping process, ensures that the locating pin 14 is pulled into the receiving sleeve 16 and, here, the planar face 22 and the end face 24 are pressed against one another. In order to ensure precise centering of the components using simple means, it is proposed according to the invention that the receiving sleeve inner cone part 34 which diverges from the cylindrical inner face toward the end face, and the locating pin supports an elastically deformable centering ring 29 which is arranged in its root region and which has an outer cone part which is complementary to the inner cone part 34.
Number | Date | Country | Kind |
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10 2005 043 850.4 | Sep 2005 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2006/008893 | 9/13/2006 | WO | 00 | 3/5/2008 |