GB2171340A - Toolholder - Google Patents

Abstract

A toolholder for rotary/percussive tools comprises a coupling sleeve (6) containing in longitudinal perforations (12) axis-parallel locking bodies (11) which, to effect axial locking, engage into closed grooves (10) of an inserted tool shaft (9). The coupling sleeve (6) together with the locking body (11) is surrounded by a sliding sleeve (7). Inside there are working surfaces which act on blocking surfaces facing them to lock and release the locking bodies (11). The working surfaces have approximately axis-parallel radial control surfaces (19, 21) which are stepped in the axial direction and which are at increasing radial distances. The locking bodies (11) are provided with corresponding axis-parallel blocking surfaces (16, 17) which are likewise stepped in the axial direction and which are in steps at increasing radial distances. As a result of axis-parallel displacement of the locking bodies (11) via the sliding sleeve (7) in relation to the fixed control surfaces (19, 21), the locking bodies (11) can move out radially and release the tool shank (9) and, conversely, move radially inwards for locking. The stepped control surfaces (19, 21) are contained in a control ring (18) fixed on the coupling sleeve (6) (Figure 1). <IMAGE>

Description

SPECIFICATION Toolholder State ofthe art The invention starts from a tool holder according to the pre-characterising clause of the main claim.

Such a toolholder is known, but it has many defects.

Thus, there are difficulties in locking an inserted tool shank automatically when the depths of the recesses in the tool shank are not coordinated exactly with the dimensions in the toolholder. Furthermore, it is only possible to insert those tools which in terms of the arrangement and number of recesses contained in them match the corresponding locations and number of locking bodies in the tool holder. If, for example, the toolholder contains four locking bodies succeeding one another at approximately equal peripheral angular intervals, the tool shank must likewise have, in a corresponding peripheral angular division, four recesses matching the locking bodies, so that such a tool can be locked in the toolholder.

The axial length of the locking bodies is limited on known tool holders, thus resulting in a relatively high wear in the region of the tool shank.

Advantages of the invention In contrast to this, the tool holder according to the invention, having the characterising features of the main claim, has the following advantages. Because of the gradation of the interacting control surfaces on the one hand and the blocking surfaces of the locking bodies on the other hand, the sliding distance of the sliding sleeve is at least substantially independent of the length of the locking bodies.

Also, despite the fact that automatic tool locking is achieved by means of genuine one-handed operation, the length of the longitudinal perforations in the toolholder is only a little greater than the length of the locking bodies themselves. Above all, the toolholder allows the locking bodies to be matched automatically to the particular depth of the recesses in the tool shank. It is thereby possible to lock perfectly even those tools which have fewer reces ses in the shankthan the toolholder contains locking bodies. Thus, for example, any tool containing only two recesses in the tool shank can be locked, even when the tool holder has four locking bodies.In this case, the two locking bodies remain in their radially outer position and rest on the outer periphery of the tool shank, whilst the othertwo locking bodies engage radially into the recesses of the tool shank, lock the latter axially and at the same time ensure the rotational take-up. Because the locking bodies are automatically matched to different depths of recesses in the tool shank, it is also possible to use those tools which have already undergone relatively high wear as regards the recesses. Afurther advantage is that the material selected for the insertion end of the tool can be inexpensive, and the tool costs can consequently be reduced. Furthermore, locking bodies of practically any length are possible, with the result that the wear of a tool shank can be reduced.

Advantageous developments and improvements of the toolholder indicated in the main claim are possible as a result of the measures listed in the following claims 2 to 39.

Drawing Exemplary embodiments of the invention are illustrated in the drawing by means of several Figures and are explained in more detail in the following description. In the drawing: Figure 1 shows a diagrammatic longitudinal section along the line l-l in Figure 2 through a toolholder with drive members of a hammer drill, according to the first exemplary embodiment, Figure 2 shows a diagrammatic perspective view of the coupling sleeve only, Figures 3 to 5 show respectively diagrammatic sections along the lines Ill-Ill, IV-IV and V-V in Figure 1, Figures Sand 7 show respectively diagrammatic sections through part of the toolholder, for example according to Figure 1, when a tool is inserted and when it is released, Figures 8 and 9 show respectively diagrammatic sections through part of a toolholder, for example correspondng to that of Figure 1, in a second and a third exemplary embodiment, Figure 10 shows a diagrammatic plan view of part of the coupling sleeve of the tooiholder of Figure 9, Figure 11 shows a diagrammatic axial longitudinal section through part of a toolholder, for example corresponding to that of Figure 1, according to a fourth exemplary embodiment, Figures 12 to 14 show respectively sections along the lines XII-XII, XIII-XIII and XIV-XIV in Figure 11, Figure 15 shows a diagrammatic perspective view of a control block of the toolholder of Figures 11 to 14, Figure 16 shows a diagrammatic perspective exploded representation of the control block and the associated locking body of the tool holder of Figures 11 to 14.

Description of the exemplary embodiments Of the hammer drill not illustrated, Figures 1 to 7 show only its drive member 2 projecting forwards from the fixed housing 1 and providing the rotary drive and an inner drive member 3 which executes the axial hammer blow.

A toolholder 5 is attached firmly to the housing 1 in a releaseable way. This toolholder 5 has a coupling sleeve 6 which, at the end on the right in Figure 1, carries a mounting flange 4 fastened to the drive member 2 by means of screws. The coupling sleeve 6 consists, for example, of steel. Guided on its outside is an axially movable sliding sleeve 7 consisting of metal or especially plastic. The coupling sleeve 6 contains on the inside a continuously cylindrical receiving bore 8, into which a tool shank 9 of a tool, for example a drill, can be inserted. The tool shank 9 has, at its rear end, a plane stop surface which is provided with a chamfer and which comes axially up against the facing stop surface of the drive member 3. The axial hammer blows are transmitted via this.

Arranged on the outer peripheral surface of the tool shank 9, at equal peripheral angular intervals from one another, are altogether four grooveshaped recesses 10 which are closed on both sides in the axial direction and into each of which engages an associated locking body 11 elongate in an axisparallel direction. Each locking body 11 is held so as to be radially movable in a longitudinal perforation 12 in the coupling sleeve 6. The longitudinal perforation 12 tapers radially inwards, so that the locking body 11 cannot fall out towards the inside. In the first exemplary embodiment, the locking bodies 11 are axially displaceable and radially movable in the longitudinal perforation 12.The movement is executed as a result of the displacement of the sliding sleeve 7 from the locking position shown in Figure 1 into the release position shown in Figure 7 and as a result of the relative displacement of the tool shank 9, inner working surfaces acting on blocking surfaces facing them to lock and release the particular locking body 11.

Each locking body 11 has a cylindrical roller 13 contained in the longitudinal perforation and a sliding block l4which covers the cylindrical roller 13 radially on the outside and which supports the cylindrical roller 13 axially at the end on the right in Figures 1,6 and 7 by means of stop lug 15 located there. In the locking position, the cylindrical roller 13 engages into the recess 10. The sliding block 14 has, on its curved outer peripheral surface, a first blocking surface 16 and a second blocking surface 17 adjoining the latter in a step. The two blocking surfaces 16 and 17 extend approximately axisparallel, and the second blocking surface 17 is stepped in relation to the first blocking surface 16 and is arranged at a greater radial distance than the latter.In the first exemplary embodiment, the stop lug 15 is located at the end of the sliding block 14 on the right in Figure 1 and projects radially inwards to such an extent that it can form an axial stop for the cylindrical roller 13.

The coupling sleeve 6 is stepped in a central region where the longitudinal perforations 12 are located. Arranged on this stepped portion is a control ring 18 secured axially on both sides. This surrounds the coupling sleeve 6 and contains, in the end region on the left in Figure 1, an inner annular surface of smaller diameter, which forms a first control surface 19, and also a second inner annular surface of larger diameter which adjoins the latter axially via a sloping step transition surface 20 and which forms a second control surface 21. It goes without saying that further stepped control surfaces can be provided between the control surfaces 19 and 21 and further blocking surfaces associated with these can be provided between the blocking surfaces 16 and 17 on the sliding block 14.

Since the control ring 18 is arranged on the coupling sleeve 6 so as to be non-displaceable axially, the control surfaces 19 and 21 are afixed component of the coupling sleeve, relative to which the sliding block 14togetherwith its blocking surfaces 16 and 17 is displaced.

The stepped portion of the coupling sleeve 6 has a first portion 22 of larger diameter, the outside diameter of which corresponds at least substantially to that of the inner annular surface of the control ring 18 forming the first control surface 19. The portion 22 has adjoining it a second portion 23 of larger diameter, the outside diameter of which corresponds at least substantially to that of the second inner annular surface of the control ring 1 which forms the second control surface 21. The first portion 22 merges into the second portion 23 by means of a truncated cone surface 24.The control ring 18 rests on the first portion 22 by means of its first control surface 19 and on the second portion 23 by means of its second control surface 21, the sloping step transition surface 20 of the control ring 18 butting against the truncated cone surface 24, and the control ring 18 consequently being supported against axial displacement to the right in Figure 1. A retaining ring 25 rests against the opposite end face of the control ring 18 and is axially displaceable on the portion 22 of the coupling sleeve 6. The retaining ring 25 is supported resiliently in the axial direction via a damping ring 26, especially a rubber ring. The damping ring 26 is supported axially on a thrust ring 27 which is held so as to be non-displaceable on the coupling sleeve 6 by means of a spring ring 28. The control ring 18 is thus also fixed axially on the left in Figure 1.

The central region of the coupling sleeve 6 carrying the portions 22 and 23 offset in the form of steps contains a number of longitudinal perforations 12 corresponding to the number of locking bodies 11,these longitudinal perforations 12 beng radially continuous and, as shown especially in Figure 2, in the front first portion 22 merging into longitudinal slots 29 located there and only open radially towards the outside. The longitudinal slots 29 do not extend radially upto the receiving bore 8.

Each locking body 11 consisting of the cylindrical roller 13 and sliding block 14 is made axially shorter than the longitudinal perforation 12 containing it, so that each locking body 11 is axially displaceable to and fro in the longitudinal perforation 12. In the locking position shown in Figure 1,the cylindrical roller 13 engages in a locking manner into the recess 10 in the tool shank 9, specifically ensuring both axial retention and torque transmission. Together with the cylindrical roller 13 the sliding block 14 is likewise located in the locking position.In the latter, the first blocking surface 16 of the sliding block 14 is supported radially on the first control surface 19, so that simply because of this the sliding block 14 and consequently also the cylindrical roller 13 cannot drift radially outwards and release the tool shank 9.

Moreover, the second blocking surface 17 of the sliding block 14 is supported radially on the second control surface 21 of the control ring 18.

In contrast to this, in the release position shown, for example, in Figure 6 or Figure 7, the first blocking surface 16 of the sliding block 14 is supported radially on the second control surface 21 of the control ring 18. The sliding block 14 is thus displaced axially to the right and at the same time also radially outwards the amount of the step between the first control surface 19 and the second control surface 21, so that the cylindrical roller 13 can pass out of the recess 10. The tool shank 9 is consequently released.

The drawings also show, on the control ring 18, between the first control surface 19 and the second control surface 21 a middle surface stepped relative to both of these. This middle surface can also serve the same control functions.

As is evident, as seen from left to right in Figure 1, the second control surface 21 follows the first control surface 19 and the second blocking surface 17 follows the first blocking surface 16. Thus, the gradation from the smaller diameter to the larger diameter takes place from left to right in Figure 1.

Since not only the cylindrical roller 13, but also the sliding block 14 is received within the longitudinal perforation 12, the sliding block 14 is thus secured in the peripheral direction.

At the end on the right in Figure 1, near the mounting flange 4, there is supported axially on the coupling sleeve 6 an approximately pot-shaped two-part spring abutment 30 which contains in recesses 31 of each sliding block 14 an approximately axis-parallel spring 32, especially in the form of a cylindrical helical spring, which by means of its end on the left in Figure 1 is supported on the facing end of the sliding block 14. In this way, each locking body 11, specifically its sliding block 14, is loaded with an axial spring force which is exerted in the opposite direction to the direction of insertion of the tool shank 9.

The sliding sleeve 7 is fixed axially in one direction on the coupling sleeve 6 by means of a spring ring 33. The sliding sleeve 7 is displaceable in the opposite direction. It has on the peripheral region of the coupling sleeve adjacent to the end on the left in Figure 1, axially directed stops 34 in the form of axially directed fingers which are aligned towards each locking body 11. The stops 34 can be in one piece with the sliding sleeve 7 or, as in the example illustrated, parts of the ring 35 which buts against the front end of the sliding sleeve 7 and is stressed by the latter. The finger-like stops 34 extend axially through the longitudinal slots 29 of the coupling sleeve 6 upto the particular sliding block 14, and in the locking position the stops 34 but against the end face of the sliding block 14 on the left in Figure 1.

When the sliding sleeve 7 is displaced to the right in Figure 1 into the release position, at the same time each individual sliding block 14 is consequently displaced axially to the right via the stops 34 from the locking position into the release position, specifically counter to the effect of the springs 32, until the first blocking surface 16 is at the height of the second control surface 21 and is supported radially on this.

Each sliding block 14 has, at the end on the left in Figure 1, radially outside the engaging surface of the particular stop 34 a sloping end face 36, the angle of which corresponds approximately to that of the sloping step transition surface 20 of the control ring 18. When the sliding block 14 has reached the release position (Figure 6), it is supported axially by means of its sloping end face 36 on the sloping step transition surface 20 in the control ring 18 and remains secured in this release position (Figure 6).

Each cylindrical roller 13 has, at the front end on the left in Figure 1, a resilient axial stop 37 which is supported on the coupling sleeve 6, that is to say is non-displaceable axially, and which projects radially into the longitudinal perforation 12 at least upto the height of the cylindrical roller 13. The axial stop 37 consists of a spring-washer part bent from wire, which extends approximately over a peripheral angle of 90!o & and engages by means of an approximately V-shaped portion (Figure 3) into the longitudinal perforation 12 and which there supports the cylindrical roller 13 on the end face at the end on the left in Figure 1. The remaining part of this spring washer part is received and supported inside a groove 38 in the retaining ring 25.In this way, the axial stop 37 is supported and damped in a resiliently elastic manner via the damping ring 26, with the result that the locking position as a whole is damped, as is the assumption of the locking position or, after the release and removal of the tool shank 9, the assumption of the unoccupied initial position.

To release the tool shank locked in Figure 1,the sliding sleeve 7 is displaced by hand to the right in Figure land the four sliding blocks 14 are displaced to the right in Figure 1 via the stops 34 counter to the effect of the particular spring 32. The sliding blocks 14 thereby slide by means of their first blocking surface 16 along the first control surface 19 and by means of their second blocking surface 17 along the second control surface 21, until a step jump, for example the sloping step transition surface 20, is reached. Each sliding block 14 then executes a radial movement corresponding to the step jump, until its first blocking surface 16 comes radially up against the second control surface 21. The cylindrical rollers 13 can thus move radially outwards and pass out of the recess 10 in the tool shank 9.The tool is released and can be pulled out completely. An associated displacement of the cylindrical rollers 13 to the left in Figure 1 is limited resiliently by the axial stop 37.

Each sliding block 14 is supported axially by means of its sloping end face 36 on the step transition surface 20, at least as long as the tool shank 9 is still located in the region of the cylindrical rollers 13. If this is not the case and if the cylindrical rollers 13 can move out radially inwards into the receiving bore 8, the sliding blocks 14 are displaced from right to left in Figure 1 again into the initial position underthe effect of the relaxing springs 32, and a sloping surface 39 at the transition between the first blocking surface 16 and the second blocking surface 17 assists by means of the slope the radial backward displacement of the sliding block 14 out of the position according to Figures 6 and 7 into that according to Figure 1, until the stop lug 15 comes up against the end of the cylindrical roller 13 on the right in Figure 1, provided that the left-hand end face of the sliding blocks 14 has not already come up against the stops 34 of the ring 35 beforehand.

When the tool shank 19 is inserted, the cylindrical rollers 13 are displaced to the right in Figure 1 via the chamfer on the right-hand end face of the tool shank 9. The cylindrical rollers 13 but against the stop lug 15, with the result that the sliding blocks 14 are also displaced to the right counter to the effect of the springs 32. During this displacement movement, the sliding blocks 14 are pushed along over the stepped curve inside the control ring 18, that is to say the first control surface 19 and second control surface 21.

When the first blocking surface 16 of each sliding block 15 reaches the second control surface 21, the cylindrical rollers 13 and sliding blocks 14 can move out radially. They open the way for the complete insertion of the tool shank 9. The tool shank 9 is pushed in along the cylindrical rollers 13 which can then penetrate into the recesses 10 in the tool shank 9. This takes place because the sliding blocks 14 are pushed forward to the left in Figure 1 along the stepped curve of the control ring 18 via the relaxing springs 32, until the locking position according to Figure 1 is assumed again, and in this the cylindrical rollers 13 are prevented from moving out radially.

The tool shank 9 is consequently locked.

The intermediate step between the first control surface 19 and the second control surface 21 is used as required. Depending on the depth of the recesses 10 in the tool shank 9, the sliding blocks 14 stop either at the first control surface 19 or at the intermediate control surface of somewhat larger diameter. The locking position of the cylindrical rollers 13 is thus determined by the depth of the recesses 10 in the tool shank 9. Coordination with recesses 10 of different depths and more or less pronounced according to the intended use in the tool shank 9 is consequently ensured.

When a tool shank 9 which, instead of the four recesses 10 shown, has only two such recesses is used, when the tool shank 9 is locked the two remaining cylindrical rollers l3stay in their outer position according to Figure 6. They then rest against the smooth outside diameter of the tool shank 9.

Because of the gradation in the form of the stair-shaped stepped curve inside the control ring 18 and, in an associated manner, on the outer peripheral surface of each sliding block 14, the sliding distance of the sliding sleeve 7 is essentially independent of the length of the individual locking bodies 11. Despite automatic tool locking, The length of the longitudinal perforations 12in the coupling sleeve 6 is also, in practice, only slightly greater than the length of the locking bodies 11. The locking bodies 11 are matched automatically to the depth of the particular recess 10 in the tool shank 9. In this way, it is possible to lock perfectly even those tools which have a smaller number of recesses 10 in the tool shank 9 than there are locking bodies 11 in the toolholder 5.A further advantage is that it is even possible to use those tools which, when employed on other hand-operated machine-tools, are already substantially worn on the tool shank 9 as regards the recesses 10 there. This is achieved because the locking bodies 11 are automatically matched to the particular depth of the recesses 10. Afurther advantage is that locking bodies 11 of practically any length are possible, with the result that the wear on the tool shank 9 is kept as low as possible. The advantage of this is also that an inexpensive material can be selected for the insertion end of the tool shank 9, thus producing reduction in tool costs. A useful benefit is also that, when a tool shank is inserted, genuine one-handed operation is guaranteed, together with automatic locking.

In the second exemplary embodiment illustrated in Figure 8, reference symbols increased by the factor 100 are used for the parts corresponding to those of the first exemplary embodiment, thus referring to the first exemplary embodiment to avoid repetition.

The second exemplary embodiment in Figure 8 differs from the first only in that the individual locking bodies 111 are all designed as one-piece elongate sliding strips 140 which, like cylindrical rollers 13 in the first exemplary embodiment, engage into a recess 110 in the tool shank 109 by means of their radially inner strip portion. The radially outer portion of the sliding strips 140 carries, on its outer peripheral surface, the first blocking surface 116 and the second blocking surface 117 adjoining the latter in a step. Because the sliding strip 140 is in one piece, there is no need here for a relative displacement in the locking body 111 which, in the first exemplary embodiment, takes place between the cylindrical roller 13 on the one hand and the sliding block 14 on the other hand. Here, the springs 132 engage on the end of the sliding strip 140 on the right in Figure 8.

The advantage of the second exemplary embodiment in Figure 8 is the simpler design of the locking bodies 111.

In the third exemplary embodiment of Figures 9 and 10, the locking bodies 211 are in two parts, as in the first exemplary embodiment. They consist of a cylindrical roller 213 and an associated sliding block 214 with a first blocking surface 216 and a second blocking surface 217. In contrasttothefirstexem- plary embodiment, however, the stop lug 215 is arranged on the front end of the sliding block 214 on the left in Figure 9. In contrast to the first exemplary embodiment, the longitudinal perforation 212 in the coupling sleeve 206 is no longer than the cylindrical roller 213 which is at least substantially nondisplaceable axially in it. At the end on the left in Figure 9, the longitudinal perforation 212 is followed by a narrower longitudinal slot 241, into which the front stop lug 215 engages.The width of the longitudinal slot 241 corresponds at least approx imatelyto that of the stop lug 215. The length of the longitudinal slot 241 corresponds at least to the axial displacement distance which the sliding block 214 covers when displaced from the locking position into the release position. The stop lug 215 engages radially through the longitudinal slot 241 and, in the locking position shown, engages into the receiving bore 208 in the coupling sleeve 206, where, when the tool shank 209 is not inserted, it forms a stop for the end face of the latter. When the tool shank 209 is inserted, the stop lug 215 engages into the recess 210 in the tool shank 209. In comparison with the first exemplary embodiment, there is no damping b means of the axial stop 37 and by means of the damping ring 26. Instead, the control ring 218, by means of its end on the left in Figure 9, is fixed axially on the coupling sleeve 206 directly via the spring ring 228. In the same way as in the first and second exemplary embodiments, the control ring 218 contains on the inside the first control surface 219 and the second control surface 221 and, between them, an intermediate control surface 242 which is mentioned at this juncture because it can be seen particularly clearly here.

In the third exemplary embodiment, when the tool shank 209 is inserted, only the sliding blocks 214 are displaced axially by the penetrating tool shank 209.

During insertion, the end face of the tool shank 209 buts by means of a chamfer against the end of the stop lug 215 on the left in Figure 9, this stop lug 215 projecting into the receiving bore 208. When the tool shank 209 is pushed in further, the sliding block 214 alone is shifted to the right out of the position according to Figure 9, until the sliding block 214 can move radially outwards and the first blocking surface 216 is supported radially on the second control surface 221, with the result that the cylindrical rollers 213 can move radially outwards, until the tool shank 209 is pushed in completely and the cylindrical rollers 213 can pass into the recesses 210. This design according to the third exemplary embodiment is also particularly simple, straightforward and inexpensive.

In the fourth exemplary embodiment according to Figures 11 to 16, each locking body 311 in the form of a one-piece sliding strip 340 has assigned to it a special control block 343 which engages over the sliding strip 340 on the outside, for example in the manner of a shoe, and which guides it by means of two lateral cheeks 344, 345. The control block 343 is axially displaceable relative to the sliding strip 340, but both parts are fixed in terms of rotation relative to one another.

Each control block 343 is guided so as to be axially displaceable and held so as to be non-rotatable radially in an approximately axis-parallel depression 346 within a guide ring 347. The guide ring 347 rests securely in the sliding sleeve 307.

The control block 343 carries, in the end region on the left in Figures 11, 15 and 16, between the cheeks 344,345 the second control surface 321 which is followed, towards the right in Figure 11, by intermediate control surface 342 and then the first control surface 319, and the latter are thus staggered at a shorter radial distance than the second control surface 321. In comparison with the first exemplary embodiment, therefore, the gradation of the individual control surfaces 319,342 and 321 of the control block 342 does not, as in the first exemplary embodiment, extend from the smaller to the larger radial dimension from leftto right, but in the opposite direction from right to left in Figure 11.

On the sliding strip 340, its first blocking surface 316 is on the right in Figure 11, and this is followed towards the left by the second blocking surface 317 of larger radial dimnension. Each control block 343 is axially displaceable to the right in Figure 11, that is to say in the direction of insertion of the tool shank 309, counter to the effect of a resiliently elastic restoring force generated by a spring 332. The spring 332 is received and centred in a pocket 348 at the rear end of the control block 343. In the control block 343, a detent lever 350 is received inside an upper cavity 349 sloping downwards towards the left in Figure 11 and is supported by means of its right-hand end in the said cavity 349 and is pivotable in it. The detent lever 350 is bent approximately at right angles at the left-hand end to form a hook portion 351.All the detent levers 350 are held in the locking position by means of a spring force acting radially from outside inwards. The spring force is exerted by an O-ring 352 which surrounds all the detent levers 350 jointly. In the locking position, the hook portion 351 of the detent lever 350 engages axially, at a distance in front of the front end of the sliding strip 340, through the longitudinal perforation 312 in the coupling sleeve 306 into the recess 310 in the tool shank 309.

The detent lever 350 has, at a radial distance from the hook portion 351, shoulders 353, 354 which project transversely on both sides and which run onto a front truncated cone surface 355 of the coupling sleeve 306 and can then run upwards along the latter, as a result of which the detent lever 350 is lifted radially from inside outwards and pivoted upwards counter to the effect of the spring force of the O-ring 352 in Figure 11, so that the hook portion 351 releases the tool shank 309.

As can be seen especially in Figures 13 and 16, the sliding strip 340 has at the front end a corner cavity 356 for receiving the hook portion 351. Arranged between the front end of the sliding sleeve 307 on the left in Figure 11 and each individual detent lever 350 is an axial compression spring 357 which transmits the sliding movement of the sliding sleeve 307 to the detent lever 350 and via the latter to the control block 343 and which holds the detent lever 350 in position.

The individual control blocks 343 are each moved via the respective detent levers 350. When a tool shank 309 is inserted, its free end buts against the hook portion 351. Consequently, when the tool shank 309 is pushed in, the detent lever 350 and via this the control block 343 are displaced from left to right in Figure 11 counter to the effect of the spring 332. When the second control surface 321 has thereby been displaced so far to the right and disengaged from the second blocking surface 317 that the sliding strip 340 can move out radially, the sliding strip 340 is thus allowed to execute a radial movement and shifts radially outwards until the first blocking surface 316 comes radially up against the second control surface 321.At the same time, the detent lever 350 is pushed outwards along the truncated cone surface 355 by means of the shoulders 353, 354, with the result that the hook portion 351 passes out of the region of the inner receiving bore 308 and opens the way for the tool shank 309 to be pushed in.

When the tool shank 309 has been pushed far enough in, the detent lever 350 and the sliding strip 340 are displaced to the left in Figure 11 under the effect of the relaxing springs 332, with the result that the tool is locked. In this locking position, the individual detent levers 350 are retained by the O-ring 352, and the shoulders 353, 354 are held up against the coupling sleeve 306.

To release the tool shank 309, the sliding sleeve 307 is displaced to the right in Figure 11. At the same time, the control block 343 and, via the spring 357, the detent lever 350 also are consequently displaced in the way described as a result of axial take-up, until they release the tool shank 309.

In this fourth exemplary embodiment again, if the tool shank 309 has, instead of four recesses 310, only two such recesses, the control blocks 343 and detent levers 350 remain in their non-locking outer position, so that, in this exemplary embodiment again, it is possible to insert tool shanks 309 having, for example, only two recesses or even only one recess.

The advantage of the tool holder according to the fourth exemplary embodiment is that, here, the locking bodies 311 can be made very long in the form of sliding strips 340. This reduces the wear.

Moreover, when the tool shank 309 is locked, the hook portion 351 can rest on the latter if, in the working position, the sliding strip 340 fills the entire recess 310 towards the left in Figure 11.

In another exemplary embodiment not shown, in a simplified version with only two sliding strips 340 the control blocks 343 can also be combined into a stepped ring.

Claims (1)

1. Toolholder for coupling striking and/or rotating tool to hand-operated machine-tools, preferably hammer drills andlor sledge hammers, with a coupling sleeve which on the one hand is connected to a drive member transmitting a drive movement and located in the hand-operated machine-tool and on the other hand receives a tool shank which has at least one groove-shaped recess closed on both sides in the axial direction, into which engages an associated locking body elongate in an approximately axis-parallel direction, which is held so as to be radially movable in a longitudinal perforation in the coupling sleeve, and with a spring-loaded sliding sleeve surrounding the coupling sleeve together with the locking body, and inner working surfaces which act on blocking surfaces facing them to lock and release the locking body, characterised in that the inner working surfaces have an axis-parallel radial first control surface (19; 219; 319) and at least one further radial second control surface (21; 221; 321) stepped relative to the first control surface (19; 219; 319) and at a greater radial distance, in that the first control surface (19; 219; 319) has assigned to it an approximately axis-parallel radial first blocking surface (16; 116; 216; 316), and the second control surface (21; 221; 321) has assigned to it a corresponding approximately axis-parallel radial second blocking surface (17; 117; 217; 317) which is stepped relative to the first blocking surface (16; 116; 216; 316) and is arranged at a greater radial distance than the latter, and in that each locking body (11; 111; 211; 311) is made at least partially axially shorter than the longitudinal perforation (12; 212; 241; 312) receiving it and is displaceable axially and radially in the said longitudinal perforation (12; 212; 241; 312) from its locking position, in which the first blocking surface (16; 116; 216; 316) is supported radially on the first control surface (19; 219; 319) or the second blocking surface (17; 117; 217; 317) is supported radially on the second control surface (21; 221; 321), into a release position, in which the first blocking surface (16; 116; 216; 316) is supported radially on the second control surface (21; 221; 321) and the recess (10; 110; 210; 310) in the tool shank (9; 109; 209; 309) is released.

2. Toolholder according to Claim 1, characterised in that, as seen in the direction of insertion of the tool shank (9; 109; 209; 309), the second control surface (21; 221; 321) and the second blocking surface (17; 117; 217; 317) respectively follow the first control surface (19; 219319) and the first blocking surface (16; 116; 216; 316), or vice versa.

3. Toolholder according to Claim 1 or 2, characterised in that each locking body (111; 311) is designed as a one-piece elongate sliding strip (140; 340) which by means of its radially inner strip portion engages into a recess (110; 310) in the tool shank (109; 309), and the radially outer portion of which carries, on the outer peripheral surface, the first blocking surface (116; 316) and, adjoining the latter in a step, the second blocking surface (117; 317).

4. Toolholder according to Claim 1 or 2, characterised in that each locking body (11; 211) has a cylindrical roller (13; 213) contained in the longitudinal perforation (12; 212) and a sliding block (14; 214) covering and at one end axially supporting the cylindrical roller (13; 213), the cylindrical roller (13; 213) engaging into a recess (10; 210) in the tool shank (9; 209), and the sliding block (14; 214), on it radially outer portion, carrying on its outer peripheral surface the first blocking surface (16; 216) and, adjoining the latter in a step, the second blocking surface (17; 217).

5. Tool holder according to Claim 4, characterised in that the sliding block (14; 214) has, at one axial end, a stop lug (15; 215) projecting radially inwards.

6. Toolholder according to one of Claims 1 to 5, characterised in that each locking body (11; 111; 211; 311) is received and is displaceable in a longitudinal slot connected to the longitudinal perforation (12; 112; 212; 312) and located in the coupling sleeve (6; 106; 206; 306).

7. Toolholder according to one of Claims 1 to 6, characterised in that each locking body (11; 111; 211; 311) is loaded by an axial spring force which is exerted in the opposite direction to the direction of insertion of the tool shank (9; 109; 209; 309).

8. Toolholder according to Claim 7, characterised in that a spring abutment (30) is supported axially on the coupling sleeve (6; 106; 206) at an axial distance from the locking body (11; 111; 211), and for each locking body (11; 111; 211) there is arranged between the spring abutment (30) and locking body (11; 111; 211) an approximately axis-parallel spring (32; 132), especially a cylindrical helical spring, which is supported on the said locking body (11; 111;211).

9. Toolholder according to one of Claims 1 to 8, characterised in that the sliding sleeve (7) carries, on the peripheral region of the coupling sleeve (6; 106; 206), stops (34) which are aligned axially towards each locking body (11; 111; 211) and by means of their free end but against the particular associated locking body (11; 111; 211), especially against the one-piece sliding strip (140) or against the sliding block (14; 214), and which, when the sliding sleeve (7) is displaced from the locking position into the release position, at the same time displace the said locking body (11; 111; 211) axially from the locking position into the release position, in which the first blocking surface (16; 116; 216) is supported radially on the second control surface (21; 221).

10. Toolholder according to Claim 9, characterised in that the stops (34) are designed as fingers which extend through longitudinal slots (29) in the coupling sleeve (6) upto the particular locking body (11; 111211).

11. Toolholder according to one of Claims 1 to 10, characterised by a sloping step transition surface (20) which leads from the first control surface (19) to the second control surface (21).

12. Toolholder according to Claim 11, characterised by a sloping end face (36) on the free end of the locking body (11), especially the one-piece sliding strip (140) or on the sliding block (14), the angle of which corresponds approximately to that of the sloping step transition surface (20) and by means of which the locking body (11), especially the sliding strip (140) of the Isiding block (14), in the release position is supported axially on the sloping step transition surface (20) and is secured in this release position.

13. Toolholder according to one of Claims 1 to 12, characterised in that each locking body (11; 111), especially the one-piece sliding strip (140) or the cylindrical roller (13), has, in its end region at the front in the pulling-out direction of an inserted tool shank (9; 109), a resilient axial stop (37) which is supported on the coupling sleeve (6; 106) and which projects into the longitudinal perforation (12).

14. Toolholder according to one of Claims 1 to 13, characterised in that the coupling sleeve (6; 106) carries a resiliently elastic damping ring (26), especially a rubber ring, on which the particular resilient axial stop (37) is supported.

15. Toolholder according to Claim 14,characterised in that the axial stop (37) consists of a spring-washer part which by means of an approximately V-shaped portion engages into the longitudinal perforation (12) and supports the locking body (11) axially on its end face, and the remaining washer part of which is supported in a groove (38) of an axially movable retaining ring (25) resting against the damping ring (26).

16. Toolholder according to Claim 14 or 15, characterised in that the damping ring (26) is supported axially by means of a thrust ring (27) which is held so as to be non-displaceable on the coupling sleeve (6) by means of a spring ring (29).

17. Toolholder according to one of Claims 1 to 16, characterised in that the stop lug (15) is arranged at the rear end of the sliding block (14).

18. Toolholder according to one of Claims 1 to 17, characterised in that the first and second control surfaces (19; 219 and 21; 221) are an axially nondisplaceable fixed component of the coupling sleeve (6; 206).

19. Toolholder according to one of Claims 1 to 18, characterised hy a control ring (18) which surrounds the coupling sleeve (6) and which contains the first control surface (19) as an inner annular surface of smaller diameter and the second control surface (21) as an inner annular surface of larger diameter.

20. Toolholder according to one of Claims 1 to 19, characterised in that the coupling sleeve (6) is made step-shaped in the middle region containing the particular longitudinal perforation (12) and on the stepped portion carries the control ring (18) secured axially on both sides.

21. Toolholder according to Claim 20, characterised in that the stepped portion of the coupling sleeve (6) has a first portion (22) of larger diameter, the outside diameter of which corresponds at least substantially to that of the first inner annular surface of the control ring (18).

22. Toolholder according to Claim 20 or 21, characterised in that the stepped portion has a second portion (23) which is of larger diameter than the first portion (22) and the outside diameter of which corresponds at least substantially to that of the second inner annular surface of the control ring (18).

23. Toolholder according to Claim 22, characterised in that the first portion (22) merges into the second portion (23) by means of a truncated cone surface (24), and the control ring (18) rests by means of its inner annular surfaces on the first portion (22) and on the second portion (23) and by means of its sloping stepped transition surface (20) buts axially against the truncated cone surface (24) in one direction and is supported on the latter.

24. Toolholder according to one of Claims 19 to 23, characterised in that the control ring (18) is held at the end facing away from the particular locking body (11) by means of a ring so as to be fixed axially in terms of displacement relative to the coupling sleeve (6).

25. Toolholder according to one of Claims 14to 24, characterised in that the control ring (18) is supported axially on the damping ring (26).

26. Tool holder according to Claim 25, characterised in that a retaining ring (25) rests against the end face of the control ring (18) and is supported on the thrust rinU (27) via the damping ring (26) arranged between them.

27. Toolholder according to one of Claims 20 to 26, characterised in that the middle region, offset in the form of a step, of the coupling sleeve (6) contains a number of longitudinal perforations (12) corresponding to the number of locking bodies (11), the said longitudinal perforations (12) being radially continuous and in the front first portion (22) merging into longitudinal slots (29) located there and open radially outwards.

29. Tool holder according to one of Claims 1 to 28, characterised in that the particular longitudinal perforation (212) within the coupling sleeve (206) has essentially the length of the respective cylindrical roller (213) which is held in it so as to be non-displaceable axially, and in that the stop lug (215) on the front end of the sliding block (214) engages into a longitudinal slot (241) in the coupling sleeve (206), the width of the said longitudinal slot (241) corresponding approximately to that of the stop lug (215) and its length corresponding at least to the axial displacement distance which the sliding block (214) covers when displaced from the locking position into the release position.

30. Toolholder according to Claim 29, characterised in that, in the locking position and in the initial position assumed after the tool shank (209) has been pulled out, the stop lug (215) projects radially through the longitudinal slot (241) and into the inner receiving bore (208) of the coupling sleeve (206) and forms a stop for the end face of a tool shank (209) to be inserted.

31. Toolholder especially according to one of Claims 1 to 30, characterised in that the first control surface (319) and the first blocking surface (316) of smaller radial dimension are arranged at the rear end, and the second control surface (321) and the second blocking surface (317) are arranged at the front end.

32. Toolholder according to Claim 31, characterised in that each locking body (311), together with its first and second blocking surfaces (316,317), has assigned to it a control block (343) which engages over the locking body (311) on the outside approximately in the manner of a shoe and which is secured against rotation, but is axially displaceable relative to the latter.

33. Tool holder according to Claim 32, characterised in that each control block (343) is held so as to be axially displaceable and non-rotatable radially in a guide ring (347) arranged fixedly in the axial direction within the sliding sleeve (307).

34. Toolholder according to one of Claims 31 to 33, characterised in that each control block (343) is guided so as to be axially displaceable in the direction of insertion of the tool shank (309) counter to the effect of a resiliently elastic restoring force, especially an axial spring (332).

35. Toolholder according to one of Claims 31 to 34, characterised by a detent lever (350) which is held pivotably on the control block (343) and which is forced by means of a radial spring force into its locking position, in which a hook portion (351) of the detent lever (350) engages axially, at a distance in front of the front end of the locking body (311), through the longitudinal perforation (312) into the recess (310) in the tool shank (309).

36. Tool holder according to Claim 35, characterised in that the radial spring force is generated buy a spring washer, especially an O-ring (352), which surrounds all the detent levers (350) jointly.

37. Toolholder according to Claim 35 or 36, characterised in that the detent lever (350) has, at a radial distance from the hook portion (351), transversely projecting shoulders (353, 354) which, when the sliding sleeve (307) is displaced from the locking position into the release position, run onto a truncated cone surface (355) of the coupling sleeve (306) and run radially outwards, at the same time pivoting the detent lever (350) relative to the control block (343) counter to the radial spring force, in such a way that the hook portion (351) releases the tool shank (309).

38. Tool holder according to one of Claims 35 to 37, characterised in that the locking body (311) has at the front end a corner cavity (356) for receiving the hook portion (351).

39. Toolholder according to one of Claims 31 to 38, characterised in that an axial compression spring (357), especially a cylindrical helical spring, is arranged between the front end of the sliding sleeve (307) and each detent lever (350).

40. Atoolholder substantially as herein described with reference to Figures 1 to 7. Figures 8, Figure 9 and 10, or Figures 11 to 16 of the accompanying drawings.