WO1993002822A1

WO1993002822A1 - Draw-in collet chuck

Info

Publication number: WO1993002822A1
Application number: PCT/EP1992/001190
Authority: WO
Inventors: Ulrich Fahrion
Original assignee: Eugen Fahrion Gmbh & Co.
Priority date: 1991-07-27
Filing date: 1992-05-28
Publication date: 1993-02-18
Also published as: JPH06509515A; EP0596892A1

Abstract

In order to reduce or, if possible, completely eliminate rotational oscillations in a machining tool held in a draw-in collet chuck and thus permit the use of a prior art collet chuck (1), in a draw-in collet chuck of the main clause the annular pressure member (7) is fitted with a guide sleeve (11), especially of the one-piece type. It overlaps a cylindrical outer casing (12) of the chuck (5) or the latter's end-piece (13) with a very small radial clearance. In particular, forcing adjusting screws (18, 24) uniformly distributed around the circumference permit the exact centring of the machining tool (2). The forcing adjusting screws are fitted, for example, between the tigthtening nut (6) and the circular pressure member (7) or between the latter or its guide sleeve (11) and the chuck (5).

Description

Title: Collet chuck

description

The invention relates to a collet chuck for a machining tool provided with a clamping shank, the shank being received by a collet whose first outer cone can be inserted into an inner cone of a chuck of a processing machine, and the collet being axially inward by means of a clamping nut placed on the chuck the inner cone can be pressed in. A collet chuck of this type is already known. When the machining tool is clamped, a total force superimposed from an axial and a radial force component is exerted on the collet. As a result, the collet is not only pressed axially into the chuck, but is also loaded transversely to its longitudinal axis. The consequence can be a side Offset of the geometric axis of the machining tool relative to the geometric axis of the tool spindle in which the chuck is inserted. Although these are only amounts in the hundredths of a millimeter range, this is not, or at least reluctantly, tolerated in view of the desired precision of the concentricity and thus also the processing.

The object of the invention is therefore to develop a collet chuck of the type described above so that an increased concentricity of the tool used therein is achieved.

To solve this problem it is proposed according to the invention that the collet chuck is characterized in that an annular pressure piece with an inner cone inserted between the clamping nut and a second outer cone of the collet carries a guide sleeve which, with little radial play, carries a cylindrical outer jacket of the chuck engages, and that between the clamping nut and the annular pressure piece or between the annular pressure piece or its guide sleeve and the chuck several, in particular evenly distributed pressure adjusting screws are connected, or that the clamping nut rests with an inner cone on a second outer cone of the collet and it carries a guide sleeve, which overlaps a cylindrical outer casing of the chuck with little radial play, and that several, in particular, between the clamping nut and an axially and radially supported ring on the chuck es particular adjusting screws evenly distributed around the circumference, or that the clamping nut rests with an inner cone on a second outer cone of the collet and partially as Guide sleeve is formed, which overlaps a cylindrical outer casing of the chuck with little radial play, that the inner cone is located on a pressure ring which is rotatably mounted axially displaceably in the guide sleeve, and that several, in particular evenly distributed on the circumference between the guide sleeve and the chuck, radial forcing adjustment screws are switched.

This group of inventions is based on the only general inventive idea, in the case of a generic collet chuck, to slide a guide sleeve onto its chuck with little radial play, which carries an annular pressure piece which, when the clamping nut is tightened, presses against the second outer cone of the collet and thereby the latter into the inner cone of the chuck, whereby the shank of the machining tool is held in a clamped manner and that a lateral offset of the geometric axis of the machining tool with respect to the geometric axis of the tool spindle in which the chuck is inserted is eliminated by means of adjusting screws.

Of course, all individual parts of this collet chuck have already been worked with the highest precision. On the other hand, you cannot do without a certain amount of play between the individual parts. The necessary tolerances between the thread of the clamping nut and the associated bolt thread have the result that, particularly in the case of thread contamination, the geometric axis of the clamping nut is laterally offset or inclined to the theoretical optimum position. This then leads to a rotationally asymmetrical loading of the second outer cone of the collet chuck by the pressure piece and thus to a misalignment of the geometric axis of the machining tool with respect to the theoretical optimal position. If, however, according to the design according to the invention, the thrust piece is provided with a guide sleeve which enables the thrust piece to be guided for a relatively long time on the chuck, an inclined position of the thrust piece relative to the theoretical optimal position becomes successful, in particular because of the close fit between this sleeve and the chuck counteracted. The game mentioned is in the order of preferably 1/100 to 2/100 mm. The longer the guide between the pressure piece and the chuck, the more favorable results can be expected. For practical reasons, there are limits.

However, because the above-mentioned play between the pressure piece and the chuck cannot completely prevent lateral displacement or tilting of the pressure piece and thus a rotationally asymmetrical loading of the collet by the pressure piece cannot be completely eliminated, a correction of the possibly existing inclined position or lateral displacement of the tool must be made the optimal location. This is easily possible with the help of the jack adjustment screws. Alignment is carried out with the aid of high-precision measuring instruments, so that a concentricity of the order of a few u is ultimately achieved. By screwing in or loosening one or more impression adjusting screws, you can achieve precise concentricity while constantly monitoring the measuring tool while slowly turning the collet chuck, similar to balancing, by applying force from the pressure piece to the collet and thus also the machining tool.

In the third embodiment, the clamping sleeve is not produced as a separate part, but is formed directly on the clamping nut. The longitudinal guide on the chuck or on their cylindrical outer jacket also takes place with very little radial play. Instead of forcing adjustment screws, adjustment screws are used there, which are primarily used as lag screws. By pulling the relevant area onto the straightening ring on the chuck, it is possible to switch off concentricity in the manner described above, which may result, for example, from contamination of the threaded connection between the clamping nut and the chuck.

Further training of this third variant and the resulting advantages and modes of action result from the subclaims.

If, however, according to the fourth variant of the invention, part of the clamping nut is designed as a guide sleeve, which enables the clamping nut to be guided for a relatively long time on the chuck, then, in particular because of the close fit between the guide sleeve and the chuck, an inclined position of the guide sleeve and thus also successfully counteracted the clamping nut compared to the theoretical optimal position.

However, because the above-mentioned play between the guide sleeve and the chuck cannot completely prevent lateral displacement or tilting of the former and thus a rotationally asymmetrical loading of the collet by the clamping nut cannot be completely eliminated, it is also necessary to correct the minimal inclination or lateral displacement that may be present of the tool in relation to the optimal position. This is easily possible with the help of the jack adjustment screws. The pressure ring is inserted into the guide sleeve with a very tight fit. Tightening an impression adjusting screw basically means an increased radial effect of the pressure ring on the collet. The radial force component of this local action effects the alignment of the tool in the direction of this radial component and thus the reduction of an undesired radial deflection of the tool in the collet. If, for example, four such adjusting screws have been staggered on the circumference, one can bpsw. the desired alignment success can be achieved by screwing in one or more screws and, if necessary, loosening one or more other screws.

A further development of a first variant of the invention provides that the clamping nut can be screwed onto the chuck and the forcing adjustment screws are connected between the clamping nut and the annular pressure piece.

Tightening an impression adjusting screw means an increased radial action of the pressure piece on the collet in this area. The radial force component of this local action effects the alignment of the tool in the direction of this radial component and thus the reduction of an undesired radial deflection of the tool in the collet. If, for example, four such adjusting screws have been staggered on the circumference, one can bpsw. the desired alignment success can be achieved by screwing in one or two screws and, if necessary, loosening one or more other screws.

In this first variant, the feed direction of the push-off adjusting screws expediently runs parallel to the longitudinal axis of the collet, wherein the adjusting screws can be screwed into the clamping nut. More specifically, are the forcing adjustment screws in the inner collar of the clamping nut, which overlaps the pressure piece from the front.

A further embodiment of the invention results from claim 4. It ensures that force is introduced at a precisely specified point.

Another embodiment of the invention describes claim 5. There, the clamping nut is rotatably but non-displaceably mounted on the chuck, so that rotation does not lead to an axial displacement of the clamping nut, but to an axial displacement of the pressure piece relative to the clamping nut and the chuck. A suitable measure prevents rotation of the pressure piece on the chuck. This can be done in a particularly advantageous manner

Pull the jack adjustment screws. Because, in contrast to the first variant, these are arranged in the radial direction and are connected between the pressure piece and the chuck, screwing in the impression adjusting screw has a direct radial effect on the assigned area of the chuck. At the same time, however, the radial pressure between the pressure piece and the second outer cone of the collet is relieved in this radial area. This must be taken into account when aligning the tool. A corresponding design of this second embodiment of the collet chuck results from claim 6.

A further development of the invention provides that the chuck is provided with a number of radial notches corresponding to the number of forcing adjusting screws, the depth of which continuously decreases from the free end face of the chuck towards the clamping nut. Adjustment screws and notches can prevent the pressure piece from turning when the clamping nut is tightened and they form the adjusting device for exact centering of the machining tool inserted into the collet, e.g. a milling cutter, drill, thread cutter and the like. When the clamping nut is loosened, the inner ends of the adjusting screws engaging in the notches are displaced towards the lower groove end and thereby loosened.

Secondly, each forcing adjusting screw carries at its inner end a peg-like extension which engages in the associated radial notch of the chuck. The diameter and length of the shoulder depend on the maximum penetration depth and the groove width.

In order to ensure a rotation of the clamping nut with axile immovability on the chuck, a further variant of the invention provides that the chuck is provided with a circumferential groove which is approximately semicircular in cross section and into which a number of balls engage, each of which is located in an outside closable radial bore of the clamping nut. Sealing can be done, for example, with the aid of threaded plugs. A rotatable but non-displaceable mounting of the clamping nut can easily be achieved in another known manner, but a ball bearing of the type described is particularly expedient because of the low friction.

A further embodiment of the invention results from claim 13. The cross section of the two grooves is semicircular, so that overall there is a circular cross section of the circumferential groove. The latter is filled with balls of corresponding diameter, so that a unit comparable to a radial ball bearing is created at this point. The pressure ring should of course Do not tilt against the guide sleeve, which can be achieved by a tight fit and a corresponding ring width. As a result, the alignment of the guide sleeve or the clamping nut can then be transmitted directly to the collet via the pressure ring.

A radial ball fill hole of the guide sleeve is expediently closable in particular by means of a stopper. The latter is known on its own and therefore does not need to be explained in more detail.

A further development of the invention results from claim 15. It ensures that when the clamping nut is loosened via the driving ring, the collet is also loosened from the inner cone of the chuck.

If a coolant and / or lubricant is provided on the chuck of the processing machine through the collet and the drill or the like. Tool, the necessary sealing must be provided in the area of the collet chuck. This applies in particular to the area of the outer end of the collet.

A further embodiment of the invention in this regard results from claim 16. In addition to the seal described there at the outer end of the collet chuck, the necessary seal must also be provided within, for example with the help of at least one O-ring, so that the liquid supplied under pressure also adopts no other undesirable location of the collet chuck can escape. In this respect, solutions are already known, which is why no further explanations are necessary here either. A further development in this regard results from claim 17. The great advantage of all the exemplary embodiments is that a collet of conventional design can be used, so no special design is necessary in this regard.

The invention is explained in more detail below with reference to the drawings. Figures 1 to 5 show five embodiments each as a half section.

In FIG. 1, a collet of conventional design picks up the shank of a processing tool 2, for example a milling cutter, drill, tap or the like, and holds it in a clamped manner. The collet 1 has a first outer cone 3 which is inserted into an inner cone 4 of a chuck 5, the conicity being of course the same in each case. The chuck 5 is, in turn, inserted in a known manner into a formally adapted receptacle of a tool spindle, not shown, of a machine tool and held therein by known means.

The clamping is achieved with the aid of a clamping nut 6. However, this does not act directly but indirectly, with the interposition of an annular pressure piece 7, on the collet 1. For this purpose, the collet also has a second outer cone 8, which is shorter than the first outer cone 3 and whose inclination is opposite to that of the first outer cone 3. The second outer cone 8 engages in an inner cone 9 of the annular pressure piece 7, both cones again having the same angle and their length or height being approximately the same size. In a known manner, the collet l is slit longitudinally several times. Between the two cones 3 and 8 there is a circumferential annular groove 10. With regard to the longitudinal slots of the collet 1, all known designs come into question. According to the invention, the annular pressure piece 7 now carries a guide sleeve 11, the latter being molded in one piece in particular. It is pushed onto the cylindrical outer jacket 12 of the free end piece 13 of the chuck 5 with little radial play. The radial play is of the order of 1/100 to 2/100 mm. Outside, the guide sleeve 11 is cylindrical and it is surrounded by the cylindrical bore 14 of the clamping nut 6, it being possible to choose a larger clearance at this point. The slight play between the end piece 13 and the guide sleeve 11, on the one hand, and the relatively long length of this guide, on the other hand, ensure that the guide sleeve 11 is attached to the chuck 5 to a large extent so as not to tip over.

At its left end in the drawing, the clamping nut 6 carries a nut thread 15 with the aid of which it can be screwed onto the bolt thread 16 of the chuck 5. Thus, rotating the clamping nut 6 in one direction causes the inner collar 17 of the clamping nut 6 to be pressed against the annular pressure piece 7, while loosening the clamping device is effected when rotating in the opposite direction. The inner collar 17 does not, however, directly press against the pressure piece 7; rather, in the exemplary embodiment according to FIG. 1, a plurality of pressure adjusting screws 18, in particular evenly distributed over the circumference, are interposed. With the usual sizes of these collet chucks, four or five such pressure adjusting screws are sufficient. The inner, frustoconical end 19 in Fig. 1 engages in a circumferential annular groove-like receptacle 20 on the outer end face 21 of the annular pressure piece 7. From this it also necessarily follows that the longitudinal axis of each impression adjusting screw 18 is preferably parallel to the geometric axis 22 of the collet chuck extends. The machining tool 2 is inserted into this collet chuck in a known manner and held in the collet 1 by clamping the clamping nut 6. The runout is then checked. Insofar as concentricity fluctuations beyond the permissible dimension are present, these are eliminated by screwing in at least one forcing adjusting screw 18 and, if necessary, unscrewing at least one other, for example diametrically opposite, adjusting screw. Measurements have shown that run-out fluctuations down to the order of magnitude of approximately less than 5 u can be reduced by adjusting the adjusting screws 18.

In the second variant shown in FIG

Clamping nut 6 rotatably but axially immovably mounted on the chuck 5. In addition, the guide sleeve 11 is slidably but non-rotatably mounted on the chuck 5 in the axial direction of the collet chuck. A rotation of the clamping nut 6 in one direction of rotation thus causes a displacement of the guide sleeve 11 in the arrow direction 23 and thus a tensioning of the machining tool 2, while a rotation in the opposite direction results in a displacement against the arrow 23, which causes the machining tool 2 to be released. As a comparison of Figures 1 and 2 shows, in the latter, the clamping nut 6 and the guide sleeve 11 are to some extent in extension from each other while in Fig. 1, the guide sleeve 11 is encompassed by the clamping nut 6, which results in a more compact, but larger in diameter Design leads. Which of the two designs you choose depends in particular on the particular use of the collet chuck. Otherwise, the same parts of the two figures are provided with the same reference numbers. 2, the guide sleeve 11 is in one piece with the annular Pressure piece 7 manufactured, which can act with its inner cone 9 on the second outer cone 8 of the collet 1.

In contrast to FIG. 1, in the exemplary embodiment in FIG. 2, the push-off adjusting screws 24 are not on the clamping nut 6, but on the guide sleeve 11 and its longitudinal axis 25 consequently runs in the radial direction.

The feed 5 is one of the number of

Forcing-adjusting screws 24 are provided with a corresponding number of notches 26, the depth of which increases from the inside to the outside or, conversely, steadily decreases from the free end face 27 of the chuck against the clamping nut 6. At their inner end, the push-off adjusting screws 24 each carry a peg-like extension 28 which engages in the associated notch 26 of the chuck 5.

While the push-off adjusting screws 24 or their peg-like extension 28 in cooperation with the associated notch 26 each not only form a device for adjusting the machining tool 2, but can also serve as an anti-rotation device for the annular pressure piece 7 or the guide sleeve 11, one acts counter-rotation of the guide sleeve 11 when tightening the clamping nut 6 in FIG. 1 by polishing at least the outer end face 21 possibly also the opposite surface of the inner collar 17 of the clamping nut 6 or providing it with a smooth surface in another known manner. In the embodiment of FIG. 2, however, the functions of aligning and securing against rotation are separated from one another by the fact that, in addition to the push-off adjusting screws 24, there are also anti-rotation screws 35 whose pin-shaped end 35 is largely free of play in the associated one Notch 26 engages. In contrast, the play of the pin-like projection 28 is greater.

The chuck 5 of FIG. 2 is provided in the area of the threadless part of the clamping nut 6 with a circumferential outer groove 29 which is approximately semicircular in cross section and into which a number of balls 30 engage. They effect the rotatable but axially immovable mounting of the clamping nut 6 on the chuck 5. So that the balls are held outwards and the game can be switched off, a locking member, for example a threaded bolt 32, is in the threaded bore 31, which receives a ball 30 turned in.

It is also possible to provide an internal groove of approximately semicircular cross section on the clamping nut 6, which corresponds to the groove 29 and provide only a single hole or threaded hole 32 for filling the balls 30. From the above it is readily apparent that the bolt thread 33, with which the nut thread 15 of the clamping nut 6 cooperates, is attached to the guide sleeve 11, in particular at its inner end.

In the second variant, the machining tool 2 is clamped in the collet 1 by turning the clamping nut 6. If impermissible run-out fluctuations are subsequently determined, one or more of the push-off adjusting screws 24 are screwed in, as in the first variant, and one or more others are slightly unscrewed if necessary.

Analogously to FIG. 2, the clamping nut 6 and the guide sleeve 11 are coupled in FIG. 1 via a number of balls 37 which are located in a circumferential annular groove. The latter exists from two halves, the clamping nut 6 and the guide sleeve 11 each having half an annular groove. The annular groove is at least slightly larger than the outer diameter of the ball in the axial direction, so that the clamping nut 6 can perform the necessary movements relative to the guide sleeve 11. But these are movements in the

Tenths of a millimeter range. A filling opening for the balls is closed by means of a threaded bolt 38. When unscrewing the clamping nut 6, the balls 37 take the guide sleeve with them. This is basically their only job.

In order to be able to detach the collet 1 from the chuck 5 in this way, a ring 40, for example a snap ring, is inserted into a groove 39 in the guide sleeve 11. It engages in the eccentric position of its bore in the annular groove 10 of the collet 1 and thus rests on the inner end face of the second outer cone 8 of the collet 1 when the clamping nut 6 is removed.

According to FIG. 3, the guide sleeve 11 is formed directly on the clamping nut 6 and is located there between the nut thread 15 and an inner cone 9 of the clamping nut 6. It lies against the cylindrical outer jacket 12 of the chuck 5 with a small radial clearance. A straightening ring 43 is inserted into an outer groove 42 of the chuck 5. So that it can be assembled, it consists of two ring halves which are connected, for example screwed together. It is held with little play both in the radial and in the axial direction, so that it can be easily rotated on the chuck 5.

A plurality of adjusting screws 44, in particular uniformly distributed over the circumference, are held on the adjusting ring 43. Each passes through a through hole 45 of the straightening ring 43 and its thread 46 is screwed into a nut thread 47 of the clamping nut 6 which is open axially towards the direction ring 43. With the aid of these adjusting screws 44, the clamping nut 6, which is slightly inclined due to contamination and thus asymmetrically acting on the collet 1, can be aligned with the chuck 5 such that an optimal concentricity of the machining tool 2 is ensured. It must be noted here that the threaded connection 15, 33 between the clamping nut 6 and the chuck 5 has a relatively large amount of play, even with training in accordance with the standards. Alignment is carried out analogously to FIG. 1 by tightening or releasing one or more adjusting screws 44 to a greater or lesser extent while simultaneously measuring the concentricity on the machining tool 2.

The head 48 of the adjusting screws 44 rests on an end face 49 of the alignment ring 43 remote from the tension nut, which, as in this exemplary embodiment, can be on the inside because of the two-part design of the ring or, in the case of another construction, the outer end face.

It can easily be imagined from FIG. 3 that the alignment ring 43 is formed by an outer collar of the lining 5. In this case it cannot be rotated relative to the feed. In order to be able to unscrew the clamping nut 6 and to be able to align the through bore 45 with a nut thread, the nut thread for the adjusting screws 44 must then be located on an auxiliary ring which is pushed onto the clamping nut 6 from the front, but which is supported on an outer collar of the clamping nut 6 on the direction of the ring must be that the necessary tensile force and thus also straightening force for straightening the possibly slightly inclined clamping nut 6 can be applied with the adjusting screws 44. In this variant, too, a ring 40, which facilitates dismantling, is used with a bore that is eccentric in the position of use, which is blown into an inner groove of the clamping nut 6.

FIG. 4 shows an advantageous development of the embodiment according to FIG. 2. The annular pressure piece 7 is extended there beyond the second outer cone 8 and there is an inner collar 51 on the extension piece. It rests against a pressure ring 52 which is inserted into the bore 54 without play . Between the pressure ring and the outer end face 55 of the collet 1 or the second outer cone 8 there is a sealing ring 53 made of resilient material, in particular of rubber, flexible plastic or the like. At least when the shank of the machining tool 2 is clamped in, this sealing ring is pressed together in such a way that that it bears in a sealing manner both on the protruding shaft part of the machining tool 2 and on the bore 54 and, due to the pressure, of course also on the outer end face 55 and the inner end face of the pressure ring 52. The main purpose of this seal is to prevent the escape of coolant which is conveyed to the machining point via the coolant channel 100 and a channel in the tool 2. It also prevents chips, moisture or even liquid from getting inside the collet chuck.

It is easy to see that such an inner collar 51 can also be attached to the clamping nut 6 of the exemplary embodiment in FIG. 1 and also the exemplary embodiment in FIG. 3, and also between this inner collar and the outer end face 55 of the second outer cone 8 of these two exemplary embodiments can use a pressure ring 52 and a sealing ring 53 as shown in FIG. 4. The variant shown in Figure 4 has the particular advantage that the pressure piece 7 only a pure sliding movement in the longitudinal direction of the geometric axis of the

Collet chuck executes and consequently the sealing ring 53 is only exposed to an axial load. In the variants of FIGS. 1 and 3, the sealing ring 6 can be loaded in the circumferential direction due to the rotary movement of the clamping nut 6 when clamping the machining tool 2.

The advantages of the long guidance of the sleeve 11 are also fully retained in the embodiment according to FIG. 4. All of the exemplary embodiments of the invention are distinguished by high concentricity. As shown in FIGS. 2 and 4, the guide sleeve 11 only executes an axial displacement movement, the concentricity is retained without restriction when the machining tool 2 is clamped. No pressure causing radial inaccuracies is exerted on the collet.

According to FIG. 5, a collet 101 of a conventional type takes up the shank of a processing tool 102, for example a milling cutter, drill, thread cutter or the like, and holds it in a clamped manner. The collet 101 has a first outer cone 103 which is inserted into an inner cone 104 of a chuck 105, the conicity being of course the same in each case. The chuck 105 is, in turn, inserted in a known manner into a formally adapted receptacle of a tool spindle, not shown, of a machine tool and held therein by known means.

Tensioning is achieved with the aid of a tensioning nut 106. However, this does not act directly, but via one Pressure ring 107 on the collet 101. For this purpose, the collet also has a second outer cone 108, which is shorter than the first outer cone 103 and whose inclination is opposite to that of the first outer cone 103. The second outer cone 108 engages in an inner cone 109 of the pressure ring 107, both cones again having the same angle and their length or height also being approximately the same size. The collet 101 is longitudinally slit several times in a known manner. A circumferential annular groove 110 is located between the two cones 103 and 108. With regard to the longitudinal slots of the collet 101, all known designs, in particular the standardized one, come into question.

According to the invention, the clamping nut is partially designed as a guide sleeve 111, i.e. the latter is molded in one piece. It is pushed onto the cylindrical outer jacket 112 of the free end piece 113 of the chuck 105 with little radial play. The radial play is of the order of 1/100 to 2/100 mm. The slight play between the end piece 113 and the guide sleeve 111, on the one hand, and the relatively long length of this guide, on the other hand, ensure that the guide sleeve 111 is attached to the chuck 105 to a large extent so as not to tip over.

At its left end in FIG. 5, the clamping nut 106 carries a nut thread 115, with the aid of which it can be screwed onto the bolt thread 16 of the chuck 105. Thus, rotating the clamping nut 106 in one direction causes the pressure ring 107 to be pressed against the second outer cone 108, while rotating in the opposite direction causes the clamping device to be released.

The pressure ring 107 is in the thread distant with little play End of the clamping nut 106 inserted and rotatable relative to the latter, but axially immovable. When clamping the machining tool 102, however, the clamping nut 106 is rotated relative to the pressure ring 107, which exerts an axial contact force on the second outer cone 108 of the collet 101. The axial entrainment takes place via a plurality of balls 137 which have been introduced into an annular groove 157. The annular groove is formed by a circumferential groove 158 of the pressure ring 107 and a circumferential inner groove 159 opposite this at the distal end of the guide sleeve or the clamping nut 106, these two grooves each having a semicircular cross section. The balls are filled in via a radial ball filling bore 160 of the guide sleeve 111, which can be closed by means of a stopper, in particular a threaded bolt 138. In an inner radial groove 139 of the pressure ring 107, a driving ring 140 is inserted, in particular blown in. This ring engages with a large distance on all sides in a radial outer groove 110 of the collet 101, which is located between the two cones 103 and 108.

The pressure ring 107 can be provided with a radially inwardly projecting inner collar 151. With its help, a pressure ring 152 and a sealing ring 153 can be pressed against the end face 155 at the outward-facing end of the collet 101. The sealing ring 153 also lies radially on the outside of the shaft of the machining tool 102 and the pressure ring 107. Because the collet 101 is radially slotted in the conventional, that is to say standardized, design, and thus lubricant and cooling liquid, which can be supplied with a corresponding design of the machine in the direction of arrow 163, can escape radially from these slits in the collet, the flow path can be shown in FIG axial direction outwards with Shut off with the help of the sealing ring 153, so that the liquid must inevitably exit via the lubrication channel or channels of the machining tool, for example a drill. This liquid can escape through other channels and gaps in a known manner, for example by means of O-rings.

A plurality of forcing adjustment screws 124 are screwed into the radial thread of the guide sleeve 111, evenly distributed over the circumference. Its inner end 161, which is suitably designed at the free end, lies against the outer circumference of the cylindrical outer shell 112 of the chuck 105. With the help of these push-off adjusting screws, the concentricity of the

Correct the machining tool 102 within certain limits after tightening. Such radial run-out errors can occur, for example, if there is an impurity in the threaded connection 115/116 between the clamping nut 106 and the chuck 105, which displaces the existing radial play on one side.

The dash-dotted line 162 indicates the shape of the clamping nut 106 or the guide sleeve 111 and the pressure ring 107 at its free end, for example, if the attachment of a sealing ring 153 and pressure ring 152 is dispensed with. If a sealing ring 153 is present, it consists of resilient material, in particular rubber, soft-elastic plastic or the like. In addition, this seal naturally also prevents chips, moisture or even liquid from penetrating into the interior of the collet chuck.

Claims

Collet chuck for a machining tool (2) provided with a collet shaft, the shaft being received by a collet (1), the first outer cone (3) of which can be inserted into an inner cone (4) of a chuck (5) of a processing machine, and the collet (1) can be pressed axially into the inner cone (4) by means of a clamping nut (6) placed on the chuck (5), characterized in that between the clamping nut (6) and a second outer cone (8) of the collet (1) an annular one Pressure piece (7) with an inner cone (9) is connected, which carries a guide sleeve (11) which overlaps a cylindrical outer casing (12) of the chuck (5) with little radial play, and that between the clamping nut (6) and the annular pressure piece ( 7) or between the annular pressure piece (7) or its guide sleeve (11) and the chuck (5) several, in particular evenly distributed over the circumference push-adjusting screws (18, 24) ltet are, or that the clamping nut (106) with an inner cone (109) on a second outer cone (108) of the collet (101) and it carries a guide sleeve (111) which with a small radial clearance a cylindrical outer jacket (112) of the chuck (105) engages, and that between the clamping nut (106) and an axially and radially supported on the chuck (105) straightening ring (143) several, in particular evenly distributed adjusting screws (144) are connected, or that the clamping nut (106) with an inner cone (109) bears on a second outer cone (108) of the collet (101) and it is partially designed as a guide sleeve (111) which overlaps a cylindrical outer casing (112) of the chuck (5) with little radial play, so that the inner cone (109) on a pressure ring (107) which is rotatably mounted axially displaceably in the guide sleeve (111) and that between the guide sleeve (111) and the chuck (105) several, in particular whose radial push-off adjusting screws (124) are evenly distributed over the circumference. 2. Collet chuck according to claim 1, characterized in that the clamping nut (6) can be screwed onto the chuck (5) and the push-off adjusting screws (18) are connected between the clamping nut (6) and the annular pressure piece (7). 3. Collet chuck according to claim 2, characterized in that the feed direction of the push-off adjusting screws (18) runs parallel to the longitudinal chuck axis (22) and they can be screwed into the clamping nut (6). 4. Collet chuck according to claim 2 or 3, characterized in that there is a circumferential receptacle (20) on the outer end face (21) of the annular pressure piece (7) for the pressure adjusting screws (18) and the engaging end of each adjusting screw (18) crowned, is frustoconical or similarly tapered. 5. Collet chuck according to claim 1, characterized in that the clamping nut (6) is rotatably but axially immovably mounted on the chuck (5) and the push-off adjusting screws (24) between the annular pressure piece (7) or the guide sleeve (11) and that Lining (5) are switched. 6. Collet chuck according to claim 5, characterized in that the feed direction of the push-off adjusting screw (24) with respect to the chuck (5) extends in the radial direction and they can be screwed into the annular pressure piece (7) of the guide sleeve (11). 7. Collet chuck according to claim 6, characterized in that the chuck (5) is provided with a number of radial notches (26) corresponding to the number of forcing adjusting screws (24), the depth of which depends on the free end face (27) of the chuck (5). steadily decreases towards the clamping nut (6). 8. Collet chuck according to claim 7, characterized in that each push-off adjusting screw (24) carries at its inner end a peg-like extension (28) which engages in the associated radial notch (26) of the chuck (5). 9. Collet chuck according to at least one of claims 5 to 8, characterized in that the chuck (5) is provided with a circumferential groove (29) which is approximately semicircular in cross section and into which a number of balls (30) engage, each of which is arranged in a radial bore (31) of the clamping nut (6) which can be closed on the outside. 10. Collet chuck according to claim 1, characterized in that the head (48) of each adjusting screw (44) is supported on the end face (49) remote from the clamping nut of the straightening ring (43) rotatably mounted on the chuck (5) and the screw thread (46) in a nut thread ( 47) can be screwed onto the end of the tensioning nut (6) on the ring side. Collet chuck according to claim 1 or 10, characterized in that the guide sleeve (11) of the clamping nut (6) is located between its nut thread (15) and its inner cone (9). Collet chuck according to at least one of claims 1, 10 or 11, characterized in that the straightening ring (43) is divided in two in the radial direction and is inserted into an outer circumferential groove (42) of the chuck (5), the two parts being screwed together by screws o. the like Fasteners. 13. Collet chuck according to claim 1, characterized in that a plurality of balls (137) are inserted into a circumferential groove (158) of the pressure ring (107) and a circumferential inner groove (159) of the guide sleeve (111) opposite this. 14. Collet chuck according to claim 13, characterized in that a radial ball filling bore (160) of the guide sleeve (111) can be closed, in particular by means of a stopper (138). 15. Collet chuck according to at least one of claims 1, 13 or 14, characterized by a driving ring (140) inserted into an inner groove (139) of the pressure ring (107) or the guide sleeve (111), which is located in a between the cones (103, 108), radial outer groove (110) of the collet (101) engages with great play. 16. Collet chuck according to at least one of claims 1 or 13 to 15, characterized in that the pressure ring (107) has an inner collar (151) and between this inner collar and the outer end face (155) of the second outer cone (108) of the collet (101) Pressure ring (152) and a sealing ring (153) are used, the pressure ring (152) being assigned to the inner collar (151) and the sealing ring (152), which is made of resilient material, lies sealingly around at least when the shank of the machining tool (12) is clamped. 17 . Collet chuck according to claim 16, characterized in that the sealing ring consists of rubber, plastic or the like. Spring-elastic material. CHANGED CLAIMS [received at the International Bureau on October 26, 1992 (October 26, 1992); Claims 10-12, 13-17 renumbered 11-13 and 15-19 replaced; added new claims 1,10 and 14; all other claims unchanged (5 pages)]

1. collet chuck for a machining tool provided with a clamping shank (2), the shank being received by a collet (1), the first outer cone (3) of which can be inserted into an inner cone (4), and the collet (1) by means of a a clamping nut (6) placed on the chuck (5) can be pressed axially into the inner cone (4), an annular pressure piece (7) with an inner cone (9.) between the clamping nut (6) and a second outer cone (8) of the collet (1) ) is switched, characterized in that the inner cone (4) is located on a chuck (5) of a processing machine, and that the annular pressure piece (7) carries a guide sleeve (11) which, with little radial play, a cylindrical outer jacket (12) of the Overlaps (5), and that between the clamping nut (6) and the annular pressure piece (7) or between the annular pressure piece (7) or its guide sleeve (11) and the chuck (5) several, in particular the same detachment adjusting screws (18, 24) distributed over the circumference.

2. Collet chuck according to claim 1, characterized in that the clamping nut (6) can be screwed onto the chuck (5) and the push-off adjusting screws (18) are connected between the t clamping nut (6) and the annular pressure piece (7).

3. Collet chuck according to claim 2, characterized. that the feed direction of the push-off adjusting screws (18) runs parallel to the longitudinal axis of the collet (22) and that they can be screwed into the clamping nut (6).

4. Collet chuck according to claim 2 or 3, characterized in that on the outer end face (21) of the annular pressure piece (7) for

Push-off adjusting screws (18) have a circumferential receptacle (20) and the engaging end of each adjusting screw (18) is spherical, frustoconical or similarly tapered.

5. Collet chuck according to claim 1, characterized in that the clamping nut (6) is rotatably but axially immovably mounted on the chuck (5) and the push-off adjusting screws (24) between the annular pressure piece (7) or the guide sleeve (11) and the feed (5) are switched.

6. Collet chuck according to claim 5, characterized in that the feed direction of the push-off adjusting screw (24) with respect to the chuck (5) extends in the radial direction and they can be screwed into the annular pressure piece (7) of the guide sleeve (11).

7. Collet chuck according to claim 6, characterized in that the chuck (5) is provided with a number of radial notches (26) corresponding to the number of forcing adjusting screws (24), the depth of which from the free end face (27) of the chuck ( 5) steadily decreases against the clamping nut (6).

8. collet chuck according to claim 7, characterized in that each push-adjusting screw (24) at its inner end 2 3

carries a pin-like projection (28) which engages in the associated radial notch (26) of the chuck (5).

9. Collet chuck according to at least one of claims 5 to 8, characterized in that the chuck (5) is provided with a circumferential, approximately semicircular in cross-section groove (29) into which a number of balls (30) engage, each of which are located in an externally closable radial bore (31) of the clamping nut (6).

10. collet chuck for a machining tool provided with a clamping shank (2), the shank being received by a collet (1), the first outer cone (3) of which can be inserted into an inner cone (4) of a chuck (5) of a processing machine, and wherein the collet (1) can be pressed axially into the inner cone (4) by means of a clamping nut (6) placed on the chuck (5), characterized in that the clamping nut (6) with an inner cone (9) on a second outer cone (8) the collet (1) rests and it carries a guide sleeve (11) which overlaps a cylindrical outer casing (12) of the chuck (5) with little radial play, and that between the clamping nut (6) and an axially and radially on the chuck (5) supported alignment ring (43) several adjustment screws (44), in particular evenly distributed over the circumference, are connected.

11. Collet chuck according to claim 10, characterized in that the head (48) of each adjusting screw (44) on the end face remote from the clamping nut (49) of the rotatably mounted on the chuck (5) bearing ring (43) is supported and the screw thread (46) in one Nut thread (47) at the ring end of the Clamping nut (6) can be screwed.

12. Collet chuck according to claim 10 or 11, characterized in that the guide sleeve (11) of the clamping nut (6) between the nut thread (15) and the inner cone (9).

13. Collet chuck according to at least one of claims 10 to 12, characterized in that the alignment ring (43) is divided in two in the radial direction and is inserted into an outer circumferential groove (42) of the chuck (5), the two parts by screws o. the like Fasteners.

14. collet chuck for a machining tool provided with a clamping shank (2), the shank being received by a collet (1), the first outer cone (3) of which can be inserted into an inner cone (4) of a chuck (5) of a processing machine, and wherein the collet (1) can be pressed axially into the inner cone (4) by means of a clamping nut (6) placed on the chuck (5), characterized in that the clamping nut (106) with an inner cone (109) on a second outer cone (108) the collet (101) abuts and it is partially designed as a guide sleeve (111) which overlaps a cylindrical outer casing (112) of the chuck (5) with little radial play, so that the inner cone (109) is located on a pressure ring (107) which in the guide sleeve (111) is axially displaceably rotatably mounted, and that between the guide sleeve (111) and the chuck (105) several, particularly evenly distributed on the circumference, push-off adjusting screw en (124) are switched.

15. Collet chuck according to claim 14, characterized characterized in that a plurality of balls (137) are inserted into a circumferential groove (158) of the pressure ring (107) and a circumferential inner groove (159) of the guide sleeve (111) opposite this.

16. Collet chuck according to claim 15, characterized in that a radial ball fill hole (160) of the guide sleeve (111), in particular by means of a plug (138), can be closed.

17. Collet chuck according to at least one of claims 14 to 16, characterized by a driving ring (140) inserted into an inner groove (139) of the pressure ring (107) or the guide sleeve (111), which is located in a between the cones (103, 108), radial outer groove (110) of the collet (101) engages with great play.

18. Collet chuck according to at least one of claims 14 to 17, characterized in that the pressure ring (107) has an inner collar (151) and between this inner collar and the outer end face (155) of the second outer cone (108) of the collet (101) Pressure ring (152) and a sealing ring (153) are used, wherein the pressure ring (152) is assigned to the inner collar (151) and the sealing ring (152), which is made of resilient material, rests all around at least when the shank of the machining tool (12) is clamped.

19. Collet chuck according to claim 18, characterized in that the sealing ring consists of rubber, plastic or the like. Spring-elastic material. _

INARTICLE 19 MENTIONED STATEMENT

The originally filed claim 1 contains several solutions to the problem. However, this group of inventions is based on a single general inventive idea, which is referred to in paragraph 2 of page 3 of the description.

With regard to the search result of the international search report, it seemed appropriate to delimit the preamble of claim 1 from the established state of the art. The demarcation was made from GB, A 551 720, listed first in the search report. The generic term of the new claim 1 does not apply to the other alternatives of the original claim 1, which is why they have been removed from claim 1 and made the subject of new, independent claims, namely the new claims 10 and 14.

Because in the subject of claim 1 (original and new version), the collet 1 is inserted into an inner cone 4 of a chuck 5, while the collet 15 of the GB, A 551 720 is inserted into an inner cone 14 of a collet, which in turn can be inserted into a Chuck of a processing machine is provided, the feature according to which the inner cone 4 is located on "a chuck 5 of a processing machine" was taken in the characterizing part of the new claim 1.

_t In the new claim 10, the reference numerals have been reduced according to an agreement with the embodiment by a factor of 100 Figure 3 which belongs to this embodiment to achieve. In this respect, the description of the drawing is consistent with FIG. 3. Claim 14 is new. It is due to the division of original claim 1.

Claims 15 to 19 correspond to original claims 13 to 17.