WO2011095362A1 - Tool and tool head for processing bores and similar removals of material - Google Patents

Abstract

The invention relates to a tool for processing bores and similar removals of material. Said tool comprises a processing side (2), a fastening side (3) and a tool shaft (1) having a rotation axis (z). The tool has a tool head (4) comprising one or more at least peripheral processing surfaces (5) and which can be rotated along with the tool shaft (1) and at least one fastening means (6) for removably fastening the tool head (4) to the tool shaft (1). According to the invention, the tool shaft (1) has a cylindrical or approximately cylindrical journal (7) arranged aligned to the rotation axis (z) of the tool shaft (1) in the region of the processing side (2). The fastening means (6) is fastened or can be fastened to the journal. The journal receives the tool head (4) having radial play. The tool head (4) is annularly shaped and is radially movable in at least one direction relative to the rotation axis (z) of the tool shaft (1) and relative to the journal (7) when in a fastened state.

Description

 Tool and tool head for machining holes

 and similar material recesses

FIELD OF THE INVENTION

The invention relates to a tool for machining bores and similar material recesses according to the preamble of claim 1.

Accordingly, the tool comprises a, preferably cylindrically symmetrical, a machining side, a mounting side and a rotational axis having tool shank, at least circumferentially one or more processing surfaces comprising the tool shaft rotatably entrained Werkzeugköpf and at least one fastening means for releasably securing the tool head to the tool shank.

Moreover, the invention relates to a tool head for a tool for machining holes or similar material recesses according to the preamble of claim 12.

Accordingly, the tool head, which is preferably part of a reamer, comprises one or more at least circumferentially arranged processing surfaces.

CONFIRMATION COPY TECHNOLOGICAL BACKGROUND

Reamers for reworking holes are well known, especially in metalworking. With a reamer, for example, the surface of a borehole wall in a metallic workpiece, in particular machined, can be machined with significantly greater demands than in the production of boreholes. This concerns less the location than the dimensions of the borehole and the corresponding tolerances. The conventional reamers are interchangeable tools that are dismantled or completely replaced after wear by machining one or more workpieces for reworking the work surfaces. The replacement of a reamer is usually coupled to a jus- day or device of the processing machine, since the reamer for post-processing a bore relative to the workpiece must be precisely aligned.

A multi-part reamer with a tool head which can be fastened on a holder for machining a workpiece can be taken from DE 10 2005 047 510 A1, CH 433 916 A, EP 0 324 909 B1 and EP 1 198 320 B1.

An essential aspect of the friction machining with regard to the quality of the borehole to be machined is a supply of cooling or lubricating or rinsing liquid in the area to be machined of the workpiece. The liquid often serves to remove both the heat generated during processing and the resulting chips, so that the processing is not disturbed thermally or by chip residues. In addition, a suitable liquid promotes a more even chip flow. In this regard, it has proven to be advantageous to equip reamers with a Flüssigkeitszu- and -durchführung. For example, reference should be made to EP 0 215 144 A1. Accordingly, the liquid transported by one or more channels in the reaming tool from the processing machine to the workpiece.

The problem with this is the associated high tool manufacturing costs, especially since it is to replace regularly exchanged wear parts in reamers. The preparation of one or more channels for coolant transport is complicated and causes high production costs. As a result, in practice, the pure tool costs take the largest share of the total costs of the friction machining. All the more so as the reamers are changed after a short service life to ensure production safety and the processing machine should be set up accordingly.

In the past, for example, the serial processing or the machining of a plurality of concentrically successively arranged bores under the specification of a high cylindricity or centricity has proven to be problematic in the friction machining of bores. In this case, positional deviations, axial alignment errors or other undesired inaccuracies can occur in the case of a reamer which is rigidly arranged on the machining tool.

To eliminate these inaccuracies and to improve the accuracy in the art pendulum reamers are encountered in which a tool is mounted oscillating on a tool holder, in particular for the automatic centering of the tool relative to the workpiece respectively for drilling. A dislocation and / or contraction of the tool on the workpiece is thereby avoided. In addition, the cost of aligning the tool is less than a rigid reamer. For this purpose, for example, the DE 34 32 615 C2 called. A disadvantage of pendulum reamers according to the prior art is the comparatively complex structure of the entire tool, which results from the fact that the tool should oscillate on the one hand and on the other hand, the above-described liquid supply should continue to be possible. So that the exchangeable wearing part does not consist of the entire tool including the liquid guide, cutting blades are arranged on a lavishly mounted tool head, which can be turned or replaced as needed. A disadvantage of this reamer with pendulum suspension are still the high tooling costs incurred by the large number of elaborate tool components as well as by a high Justage- and mounting effort of the cutting blade.

In addition, pendulum reamers, as can be found in various designs in the prior art, are often characterized by high (fault) susceptibility. For example, imbalances can occur when changing the cutting blades, which reduces the machining quality. In addition, there is the fact that the complex pendulum reamers form a comparatively massive tool, which is particularly influenced by its own weight in horizontal tool guidance such that high demands on the quality of machining, especially when aligned as precisely as possible holes can not be achieved. In conjunction with the necessary rotational speeds of the tool and due to the complex construction of the pendulum reamer long discharges of the tool and the associated tendency to clamp in the mechanics of the pendulum holder, inaccuracies and disturbances up to a tool break arise.

Against this background, the invention is based on the object of specifying a tool for machining bores and similar material recesses, which is simplified in such a way that it can be produced inexpensively, without significantly impairing the machining quality and / or the service life of the tool become. This object is achieved by a tool according to claim 1. Accordingly, it is provided that the tool shank of the tool has, in the region of the machining side, a cylindrical or approximately cylindrical pin arranged in alignment with the axis of rotation of the tool shank. At the pin fastener is attached or fastened. The pin receives the tool head with radial play. The tool head comprises an annular region and is displaceable in the fastened state in at least one direction, in particular in a first direction, radially with respect to the rotational axis of the tool shank and relative to the journal.

The tool is particularly suitable for machining and preferably serves as a reamer. It is expedient if the tool shaft and the pin are integrally formed, for example, as a rotating part of metal. However, the pin and the tool shank may also consist of two parts, in particular the pin may be formed wholly or partly by the shank of a screw which receives the tool head with radial play. The machining surfaces of the tool head may, for example, have cutting edges, wherein the machining surfaces are an integral part of the tool head. Additional cutting elements such as (indexable) inserts or blades and their attachment accessories are possible but not required. This significantly reduces the risk of the tool head causing an imbalance. In addition, manufacturing and operating costs are reduced by these simplifications according to the invention. The tool head thus forms a low-cost, one-piece wear and replacement component, in particular made of hard metal, with an annular region predeterminable axial length, which has a comparatively small size and a comparatively small volume, whereby significant material costs can be saved. In this respect, the invention is also suitable for processing machines in which one-way pendulum friction heads are to be used to increase production reliability. The tool according to the invention is characterized by highest simplicity. The tool shank, which may be formed of a less expensive material than the tool head, can be used for a significantly longer service life. Replacement of the tool head after wear can be done by loosening a (single!) Fastener. The replacement can take place on the machine, which is a decisive advantage in transfer lines, inter alia, since a machine-related downtime can be completely avoided. As a result, the cost of tool change is also significantly reduced, which makes itself felt favorably in the processing costs. In addition, there is the advantage that the tool can be manufactured with little effort due to the small number of components.

The lateral displaceability of the tool head with respect to the pin and thus with respect to the fixed and possibly releasably connected to the pin tool shank allows a pendulum-like movement of the tool head radially to the bore. Thereby, an improvement of the adjustment of the tool position is achieved at the position of the bore, as well as an improvement of the roundness and the cylindricity of the reworked by the reaming hole. Such an improvement is also achieved in a horizontal tool guide, since the tool has a relatively low weight due to the simple structure with few components. In the case of a machine horizontal feed, the tool head fastened to the tool shank experiences a significantly lower vertical deviation compared with the prior art, as a result of which axial alignment errors in the friction machining of workpieces can be avoided.

Expediently, the tool head can have a central bore, which is aligned with the axis of rotation, for receiving the journal, with a complete through-bore or opening being advantageous with regard to the releasable attachment. In an advantageous embodiment of the tool according to the invention can be provided that in the transition region between the tool shank and pin is formed a perpendicular to the axis of rotation arranged contact surface of the tool shank. Between the tool head and the contact surface, a driver ring with radial play can be arranged on the journal. The tool head can be displaced radially relative to the axis of rotation at least in the first direction relative to the driving ring. The driving ring can be displaced in at least one direction, in particular in a second direction, radially with respect to the axis of rotation. Preferably, the first direction and the second direction are perpendicular or approximately perpendicular to each other, wherein by the first direction and the second direction, a plane is transverse to the axis of rotation of the tool shank, in particular perpendicular or approximately perpendicular, and to its contact surface parallel or approximately runs parallel.

The driving ring can - as well as the tool head - have a central opening or opening, in particular in the form of a bore, whereby the driving ring can be plugged onto the pin. Both the central opening of the driving ring and the tool head have a slightly larger diameter than the pin. Thus, driving ring and tool head relative to the pin a predetermined radial play. By the decomposition of the common radial movement of the parts combination of driving ring and tool head in two components of movement, namely the driving ring and the tool head, the rotatably mounted on the driving ring tool head has the ability to "swing" in any radial direction relative to the tool shank , By "pendulum" here means a, preferably purely linear, reciprocating motion in the plane which is preferably perpendicular to the axis of rotation. During this movement of the tool head, the inclination of the head with respect to the tool shank and thus also with respect to the workpiece to be machined is not changed. This is a decisive advantage for precise and reproducible workpiece machining. About that In addition, avoiding a tilting of the tool head leads to an extension of the service life of the tool shank, since it is exposed to lower loads. This also reduces the tooling costs during workpiece machining.

It may be expedient if at least one recess extending perpendicular or approximately perpendicular to the axis of rotation is arranged in the contact surface through which at least one tool driver surface is formed, to which a driver located on the driver ring engages, in particular in the form of at least one web , As a result, tool shank and driver ring are arranged rotatably by driving with each other. The driving ring is thereby displaceable along the recess radially with respect to the axis of rotation. Thus, the rotationally fixed arrangement of the tool head to the drive ring can be realized in a simple to produce and thus cost-effective manner. It may be expedient if two mutually opposite tool driving surfaces of the recess are inclined relative to the contact surface, in particular relative to each other. The recess is preferably narrower at its end facing the fastening side than at its end facing the machining side. The contour of the recess substantially corresponds to the contour of the tool driver. This embodiment offers the particular advantage that in the manufacture of the tool according to the invention by the post-processing of the bevels of the tool driving surfaces and the tool driver, the fit between the web and recess can be precisely adjusted. On the one hand, this fit must not be too tight, since the drive ring and tool shank are otherwise not displaceable relative to one another. Nor should the fit have too much play, since the drive ring can otherwise slip uncontrollably on the shaft. The oblique arrangement of the surfaces here offers the opportunity to meet the requirements of the fit with the highest possible accuracy while keeping the size of the friction surfaces adjacent to each other as small as possible and the least possible effort. By analogy with this, it can also be expedient with regard to the manufacturing outlay if a groove running essentially perpendicularly to the rotation axis is arranged as a cutout in the tool head, by which at least one tool head driving surface is formed, to which one on the tool shaft or on a driving ring arranged tool driver attacks. As a result, the tool head and driving ring are arranged rotationally fixed relative to one another. The tool head is thus displaceable along its groove radially with respect to the axis of rotation.

An additional advantage with regard to the adaptation of the tool driver to the groove of the tool head is obtained when two mutually opposite tool driving surfaces of the groove relative to the contact surface, in particular relative to each other, obliquely, and if the groove preferably facing at its the machining side End is narrower than at its the fastening side facing the end. The contour of the groove should essentially correspond to the contour of the tool head carrier web.

In a further embodiment of the tool according to the invention, the driving ring on at least one franking, which is preferably arranged in the region of the tool driver. The franking is mechanically not further processed for cost savings during the production of the tool.

In a preferred embodiment of the tool, a radial movement ensuring axial clearance is provided, which is effective in the region of the pin on the tool head. Depending on the configuration of the tool, the axial gap can be arranged between the tool head and the fastening means, and / or between the tool head and the tool shaft. An arrangement of the gap between the tool head and the driver ring and / or between the driver ring and the tool shank may also be appropriate. The desired radial play in the area between the pin and the tool head and / or the driving ring is ensured by a radial gap. This radial gap is expediently arranged between the journal and the central opening of the tool head. A gap with a preferably identical gap dimension can also be provided between the driver ring and the journal. With regard to the production of the radial gap can be formed in that the central opening in the tool head or in the driving ring has a suitably larger diameter or have as the pin. The diameter difference corresponds in this embodiment twice the gap.

It may be useful if the fastening means for fixing the tool head on the tool shank respectively on the pin is formed as a screw head, wherein the associated screw shaft engages in an arranged in the pin, aligned with the axis of rotation threaded hole in the pin. Optionally, any other attachment may be provided, such as a nut which engages in an external thread of the pin, or a snap ring which engages in a fastening groove arranged circumferentially in the pin. In the event that the fastening means is formed as a nut or as a snap ring, the pin should have an extension which is greater than the depth of the central opening of the tool head or greater than the sum of the openings of the tool head and driving ring. The mounting groove for the snap ring or the thread for receiving the nut is then arranged in the extension of the pin. Instead of the pin, the shank can serve a screw which can be screwed into the tool shank or a comparatively short pin stub.

In one embodiment of the tool according to the invention can be provided for the purpose of tick cooling, flushing and / or lubrication that is arranged in the tool shank at least one liquid channel for the transport of liquid. The fluid channel extends substantially from the attachment side to the processing side. In the area of the processing side opens the liquid channel in at least one liquid outlet, which is preferably arranged in the region of the pin. Optionally, the fluid channel can pass through the pin. In particular, when using a nut or a snap ring, it may be expedient if at least one liquid outlet is arranged in the end face of the pin. In this case, the exiting liquid can rinse out the chips formed in the bore formed by the tool particularly effectively. If necessary, the front side arranged liquid outlet can be closed by a detachable in the liquid outlet sealing screw. As a result of the arrangement of the liquid channel in the tool shank, liquid channels in the tool head can at least largely be dispensed with, as a result of which the manufacturing costs of the tool head can be further reduced.

The liquid may also be a cooling liquid to which the heat generated during workpiece machining can be transferred and thus transported away. Alternatively, the fluid channel may also be suitable for conveying a liquid or low viscosity lubricant which lubricates the tool during processing. The fluid channel can optionally have at least one branching and / or angling within the tool housing, as a result of which the fluid can be distributed over a larger area within the tool shaft. The liquid outlet or the liquid outlet may preferably lead to the first, the second gap or to a franking. Thus, the liquid is optimally distributed between the tool components and between the tool and the workpiece.

The invention also provides a tool head for machining bores or similar material recesses according to claim 12. According to the invention, the tool head has a central opening extending in the axial direction, whereby it can be plugged onto a journal, in particular onto a journal of one or more embodiments of the above-described tool , The tool head is a wearing part, wherein in particular the working surfaces of the tool head are worn. Depending on the shape, nature, material and number, it may be provided that the processing surfaces are nachschleifbar. Due to the fact that the tool head is comparatively simple in construction and has no complicated fastening devices for additional cutting elements, it can be manufactured as a cost-effective mass part. The working surfaces may be hardened, in particular they may be formed of a harder material than the rest of the tool head and / or the tool shank. Alternatively, the entire tool head may also be formed from a hard metal. The processing surfaces are part of the tool head, ie tool head and processing surfaces are preferably integrally connected. The processing surfaces may have cutting surfaces or edges with which a workpiece is machinable. Advantageously, the tool head is formed rotationally symmetrical at least in its contour lines. In particular, it does not generate any imbalance during rotation.

In a preferred embodiment of the tool head according to the invention it can be provided that the opening comprises at least one cone. The cone may be continuous or be formed as in relation to the depth of the opening in a central region converging double cone. With a conical opening, the production of the tool head is simplified, whereby the manufacturing costs are reduced. An abrasive machining in the manufacture or completion of the cone or the double cone of the opening of the tool head may be necessary insofar as the opening or the central bore of the tool head is preferably to have a nominal size, which is greater according to the desired radial clearance than the narrowest cross-section the opening associated outer diameter of the pin on which the tool head can be plugged. Set the exact nominal size by grinding. It may be expedient if teeth are arranged on the tool head on the circumference, which comprise the processing surfaces. Through the teeth becomes the tool head overall easier, since it is made of less material to manufacture. This also has a favorable effect on the (manufacturing) costs, in particular since the tool head can be formed from high-priced materials such as hard metal alloys, a high-speed steel and the like. At the same time the surface of the tool head is enlarged by the teeth, whereby a better heat dissipation is possible. The tool head is thereby better cooled, whereby the service life of the tool head is extended. The teeth may optionally be arranged obliquely or comprise a bevel, are arranged on the processing surfaces.

In a preferred embodiment of the tool head according to the invention can be provided that the central cylindrical or conical or biconical opening in the tool head comprises a crank. The offset is suitable, for example, for receiving a fastening means such as a screw head. As a result, the fastener is also better protected during machining of the workpiece with the tool head, whereby the fastener less disturbs and a tool head exchange is possibly facilitated. An unprotected fastening means may become dirty or sticky, for example due to coolant or lubricating fluid, which may require a greater outlay in loosening the fastening means when changing tools.

Particularly when using the tool head for a tool with one or more liquid channels, it can be provided with particularly high-quality tool heads that at least one liquid channel is provided for transporting liquid through or along the tool head, wherein the liquid channel is coupled in particular to a liquid outlet of the tool or can be coupled. Thus, a cooling, lubricating or rinsing effect of a guided through the tool liquid to the tool head is expandable. In particular, the fluid channel may extend into one or more of the teeth of the tool head. The above-mentioned and the claimed components to be used according to the invention described in the exemplary embodiments are not subject to special conditions of size, shape, material selection and technical design, so that the selection criteria known in the field of application can be used without restriction

Further details, features and advantages of the subject of the invention will become apparent from the dependent claims, as well as from the following description and the accompanying drawings, in which - by way of example - an embodiment of a tool and a tool head are shown. Also, individual features of the claims or of the embodiments may be combined with other features of other claims and embodiments.

BRIEF DESCRIPTION OF THE FIGURES In the drawing

1 to 3 show first to third embodiments of a tool for processing bores and similar material recesses in axial section;

Fig. 4 of the tool of Figure 1 is a perspective view; Fig. 5 of the same tool a side view;

Fig. 6 of the same tool an end view;

Fig. 7 of the same tool a side view of a tool head; such as Fig. 8 shows an alternative embodiment of the tool head in axial section.

DETAILED DESCRIPTION OF EMBODIMENTS

FIG. 1 shows a tool for machining bores and similar material recesses. It is particularly useful as a reamer. The tool comprises a substantially cylindrically symmetrical tool shank 1, which has a machining side 2 at its one, for example the upper, end and an attachment side 3 at its other, for example the lower, end. The machining side 2 is used to machine a workpiece, for example can be a Reibbearbeitung a hole in the workpiece. On the mounting side 3, the tool is clamped in a holder of a machine with rotary drive. Relative to the workpiece, the tool rotates about its axis of rotation z and / or undergoes a linear feed in the z-direction.

In the area of the machining side 2, an annular tool head 4 is arranged on the tool. On the circumference, there are a plurality of machining surfaces 5 on the tool head 4 for machining or grinding the preferably metallic workpiece. In particular, at the machining-side end (2) of the tool head 4 and the processing surfaces 5, a bleed 36 may be provided in each case. The gate 36 may be disposed at an angle to the rotation axis z which is in a range of 0.1 ° to 85 °, preferably 0.3 ° to 15 °. The gate 36 may have one or more sections, wherein the angle of the sections may be different from the axis of rotation z. Optionally, each processing surface 5 in the region of the gate 36 may have cutting or cutting properties. The working surfaces 5 of the tool head 4 are stressed during the friction machining of the workpiece and worn over time. The tool head 4, which is shown in detail in Figures 4, 7 and 8 and described below, is fastened to the tool with a fastener 6. The fastening means may in particular be a screw head 8A (FIGS. 1, 4 to 6 and 8), a nut 10 (FIG. 2) or a clamping or snap ring 15 (FIG. 3). When attaching it is a detachable attachment so that the tool head 4 of the tool is interchangeable. In this way, the service life of the tool shank 1 is increased, whereby the total cost of the friction machining is significantly reduced. Only the tool head 4 forms a regularly exchangeable wear part, the other tool components can be used for a considerably longer period of friction.

For the detachable arrangement of the tool head 4 on the tool shank 1, the tool shank 1 in the region of the machining side 2 has a cylindrical pin 7 which is aligned with the axis of rotation z of the tool shank 1. The fastening means 6 can be fastened to the journal 7 (FIGS. 1 to 6) or the journal is formed by a screw shaft 8B which carries a screw head 8A serving as a fastening means. The tool head 4 can be arranged rotatably by driving elements with respect to the pin 7. A driver ring 20 which can be used for this purpose and which is explained in more detail in connection with FIG. 4, preferably also sits on the journal 7 or on an extension of the tool shaft on this side for this purpose.

It can be seen from FIG. 1 that the fastening means 6 can be formed as a screw head 8A, preferably with a hexagon socket, whose associated screw shaft 8B engages in a threaded bore 9 arranged in the pin 7. The threaded hole 9 and the rotation axis z lie in alignment. For simplified determination of the axial effective length of the pin 7, the screw head 8A in its end position on its tool head side on a stop means of the pin 7, such as an end face, come to rest. By loosening and removing the screw 8, the tool head 4 can be removed from the pin 7 and replaced with a new head. Thus, to Tool change no further fasteners are operated, whereby the tool change can be performed quickly and easily. The tool change-related service life interruption is thereby reduced to a minimum. The screw head 8A is tightened against the end face of the pin 7.

An alternative attachment of the tool head 4 on the pin 7 can be seen in FIG. There is a nut 10, in particular a hex nut provided as a fastening means 6. The nut 10 engages via an external thread 11, which is arranged on an extension 12 of the pin 7 arranged in the region of the machining side 2 of the tool, which projects beyond the end face of the tool head 4 facing the machining side 2 and carries an external thread.

It can also be seen from FIG. 2 that an axial gap 13 can be arranged between the tool head 4 and the fastening means 6, which permits a minimal axial clearance of the tool head 4. The axial play causes the tool head 4 to move radially relative to the tool shank 1 sufficiently easily. Optionally, the axial gap 13 can also be arranged in a region between the tool head 4 and the tool shank 1. The dimension of the axial gap 13 and thus of the axial play is preferably 0.001 to 1.0 mm and particularly preferably 0.01 to 0.03 mm. To produce an all-round sufficient radial play and mobility of the tool head 4 relative to the tool shank 1 or the pin 7, a radial gap 14 is provided in the region of the pin 7. The radial gap 14, which can also extend to the driver ring 20 is formed by the fact that the inner diameter of the tool head 4 and the driver ring 20 is greater than the outer diameter of the pin 7. The diameter difference corresponds to twice the size of the second gap 14, which is preferred 0.001 to 1, 0 mm and more preferably 0, 1 to 0.2 mm may be. Due to the radial clearance of the tool head 4 can be moved radially relative to the tool shaft 1. This shift essentially takes place in the xy plane and allows, for example, a compensation tion of axial alignment errors when rubbing holes in a workpiece.

In Fig. 3, a releasable snap ring 15 is shown, which engages in a receiving side in the pin 7 arranged on the attachment groove 16. The groove of the mounting groove 16 is made so that between the tool head 4 and tool shank 1 can set the required axial overall play. The snap ring forms an alternative fastening means 6 to the screw 8 according to FIG. 1 or the nut 10 according to FIG. 2. The fastening groove 16 is also arranged on an extension 11 of the pin 7. The use of a snap ring 15 leads to a further cost and weight reduction of the tool according to the invention compared to the above-described attachment variants. At the same time, the snap ring 15 has the advantage that, in contrast to the screw 8 or the nut 10, it can not loosen or loosen by the movements of the tool itself.

FIG. 3 also shows an example of the guidance of a liquid channel 17 for transporting a cooling, rinsing or lubricating liquid. The attachment of the tool head 4 by means of a snap ring 15 allows a more varied guidance of the liquid channel 17 as in a fastening by means of a screw 8 as shown in FIG 5. As shown in FIG. 3, the liquid channel 17 may extend substantially from the mounting side 3, where it on a Liquid supply can be connected, to the processing side 2, where the liquid leaves the liquid passage 17 at one or more Flüssigkeitsaustritt / en 18. The liquid outlets 18 are arranged in the region of the pin 7 so that the liquid around the driving ring 20 and / or the tool head 4, for example, or backwash, wherein, preferably, the one or more radial gaps can serve as a distributor. Thus, on the one hand optimal cooling of the tool head 4 is effected, and on the other hand, the chips produced by the tool head 4 are removed from the processing surfaces 5. Both effects lead to an improvement in the quality of the workpiece machining and to an extension of the life of the tool, in particular the tool head 4. It is also advantageous to lead the liquid channels in the machining side 2 exclusively or predominantly by the pin 7 and not or only to a small extent by the tool head 4. In the end face of the extension 12 of the pin 7, a sealing screw 27 for closing the axially opening Liquid channel 17 may be provided. If, for example, a through bore of a workpiece is to be reworked with the tool according to FIG. 3, an opening of the frontally terminating liquid channel 17 can be expedient insofar as chips are flushed out of the through bore together with the liquid emerging from the end face. If, alternatively, a blind bore is to be reworked with the tool according to FIG. 3, it is advisable to close the end-side liquid outlet with the sealing screw 27, since otherwise a fluid congestion would form in the blind bore which could be an obstacle to high-quality reworking of the blind hole ,

A perspective view of a tool according to FIG. 1 can be taken from FIG. 4. There it can be seen that in the transition region between the tool shank 1 and pin 7, a contact surface 19 of the tool shank 1, which is arranged substantially perpendicular to the axis of rotation z, is formed. Between the tool head 4 and the contact surface 19, a driver ring 20 is arranged on the pin 7. The driver ring 20 is rotatably arranged by driving elements with respect to the pin 7 and preferably also with respect to the tool head 4 of Fig. 4 it can be seen that the tool head 4 in a first direction x relative to the driver ring 20 radially relative to the axis of rotation z is displaceable. The driving ring 20 is radially displaceable in a second direction y with respect to the axis of rotation z. The first direction x and the second direction y are perpendicular to one another and span an xy plane which is perpendicular to the rotation axis z of the tool shank 1 and parallel to the abutment surface 19. In the contact surface 19, a recess 21 extending perpendicularly to the axis of rotation z is arranged through which the tool driver surfaces 22 are formed. At the tool driver surfaces 22 engages a driver ring 20 arranged on the first tool driver 23. As a result, the tool shaft 1 and the driving ring 20 are rotatably arranged by driving with each other. In addition, thereby the driving ring 20 along the recess 21 radially relative to the axis of rotation z is displaced.

It can be provided that the two mutually opposite tool driver surfaces 22 of the recess 21 extend obliquely relative to the contact surface 19, in particular relative to one another. The inclination of the tool driving surfaces with respect to the vertical should be less than 15 °. It is preferably between 0 ° and 1 °, for example 0.1 °. In addition, the recess 21 may be narrower at its end facing the fastening side 3 than at its end facing the machining side 2. Conveniently, the contour of the recess 21 should substantially correspond to the contour of the tool driver 23.

According to FIG. 4, a recess 24 running vertically to the rotation axis z is arranged in the form of a groove in the tool head 4. Through the groove tool head driving surfaces 25 are formed, to which a driver ring 20 arranged as a web trained tool driver 26 engages. As a result, tool head 4 and driving ring 20 are arranged rotationally fixed relative to one another. The tool head 4 is displaceable radially along the groove with respect to the axis of rotation z.

In particular, at the machining-side end (2) of the tool head 4, at least one centering aid 37 can be provided, with which the centering of the tool head 4 in the bore to be machined or the material recess to be machined is facilitated and improved. The centering aid 37 may comprise a center chamfer 37A, which is arranged on the outside at one end, in particular at the machining-side end (2) of the tool head 4. The centering Chamfer 37A may be formed by a chamfered surface disposed in the region where the machining surfaces 5 merge into the machining-side end surface of the tool head 4. The inclination of the tapered surface of the centering bevel 37A relative to the axis of rotation z may be between 5 ° and 85 °, preferably between 40 ° and 50 °. Alternatively, the centering aid 37 may comprise a rounded tool edge, ie a centering rounding (not shown). Optionally, the machining surfaces in the region of the centering aid 37 may be such that they have neither cutting nor cutting properties, but rather are dull, whereby the centering is further facilitated.

Advantageously, the two opposite tool head driving surfaces 25 of the groove extend obliquely relative to the contact surface 19, in particular relative to one another. In particular, the groove is narrower at its end facing the machining side 2 than at its end facing the fastening side 3. The contour of the groove should substantially correspond to the contour of the tool driver 26.

The displacement of the tool head 4 relative to the tool shank 1 or the pin 7 results from the execution of the tool according to FIG. 4. Any displacement is composed of a displacement of the tool head 4 in the first direction x and a displacement of the tool head 4 Tool head 4 in combination with the rotationally fixed thereon driving ring 20 in the second direction y. By combination of both displacements in the x and y directions, the tool head 4 can be displaced as desired radially relative to the pin 7.

4, the clearances 30 can further be removed, which are arranged on the driver ring 20. The clearances 30 are located on the tool driver 26 and on the tool driver 23. A side view of a tool can be seen in FIG. 5. The attachment of the tool head 4 corresponds to the attachment described in FIG. Dashed lines in Fig. 5, the liquid channel 17 is shown. The channel has a branch 28. As a result, the liquid can be transported in a larger area of the tool. It can also be seen from FIG. 5 that in the tool head 4 at least one liquid channel 29 for transporting the liquid is arranged in particular longitudinally through the tool head 4. The liquid channel 29 couples to one of the plurality of liquid outlets 18 of the tool in the region of the contact surface 19 of the tool shank 1. The liquid channel 29 ends in the region of the fastening means 6, which is formed as shown in FIG. 5 as a screw 8. As a result, the axial gap 13 is acted upon by liquid between the fastening means 6 and the tool head 4, which additionally facilitates the lateral movement of the tool head 4 relative to the pin 7. In addition, the processing surfaces 5 of the tool head 4 are better cooled by the liquid head channel 29, whereby the service life of the tool is increased.

FIG. 6 shows a plan view of a tool according to FIG. 5. The tool head 4 fastened with a hexagon socket screw 8 comprises teeth 35 arranged on the circumference and on which the machining surfaces 5 are arranged. It can also be seen from FIG. 8 that the liquid outlets 18 are arranged in the region of the teeth 35. A total of one liquid outlet 18 can be provided or one liquid outlet 18 per tooth 35. According to FIG. 6, a tool head 4 with 8 teeth 35 is provided. Also visible is the tool driver 26, on whose sides in each case a franking 30 is arranged.

A side view of a tool head 4 for machining bores or similar material recesses for a tool, in particular according to FIGS. 1 and 5, is shown in FIG. The processing surfaces 5 are arranged circumferentially on the tool head 4. The ratio length / diameter of the Tool head 4 should be smaller than 1, 5. Preferably, the length / diameter ratio is in a range between 0.2 and 1.5.

A vertical section through another tool head 4 according to the invention can be taken from FIG. 8. This tool head also has an opening 31 extending in the axial direction, whereby the tool head 4 can be placed on the screw shank 8B of the tool serving as a pin in the sense of the invention, while the screw shank 8B, leaving the necessary axial length for receiving the tool head and optionally 8 for the reception of a driver ring 20, not shown in FIG. 8, ie, up to a predetermined axial effective length, can be inserted into the tool shank 1 or a trunnion stub. It can also be seen from FIG. 8 that the opening 31 comprises a first conical surface 32. The inclination of the side wall of the opening 31 with respect to the vertical, ie with respect to the axis of rotation z, may be less than 5 °. Preferably, the angle of inclination of the side wall of the opening 31 has a value between 0.1 ° and 2 °. Thus, the opening angle of the cone surface 32 is in a range between 0.2 ° and 4 °. By the conical surface 32, the diameter of the opening 31, for example, on the machining side, ie in the direction of the machining side 2, greater than in the direction of the mounting side 3. Alternatively or additionally, a second conical surface 34 may be provided with a comparable or larger opening angle, the opening 31 thereby may have their smallest diameter in a central region. It can also be seen from FIG. 8 that the tool head 4 for receiving the fastening means 6 can have a cylindrical offset 33. The conical surface 34 adjoins the offset 33, wherein the diameter of the conical surface 34 on the machining side is greater than on the fastening side. The angle of inclination of the side surface of the crank 33 with respect to the vertical, ie with respect to z, should be less than 15 °. It is preferably between 0.1 ° and 15 °. LIST OF REFERENCE NUMBERS

1 tool shank 22 tool driver surface

2 processing page 23 first tool driver

3 mounting side 24 recess

 4 tool head 25 tool head

5 working surface driving surface

 6 fastener 26 second tool driver

7 pin 27 sealing screw

 8 screw 28 branch

 8A screw head 29 fluid channel

 8B screw shaft 30 franking

 9 threaded hole 31 opening

 10 nut 32 conical surface

 11 external thread 33 offset

 12 extension 34 conical surface

 13 axial gap 35 tooth

 14 Radial gap 36 Bleed

 15 Clamp or snap ring 37 Centering aid

 16 mounting groove 37A centering chamfer

 17 fluid channel

 18 Fluid outlet X first direction

 19 contact surface y second direction

 20 driving ring z rotation axis

 21 recess

Claims

1. A tool for machining bores and similar material recesses with a processing side (2), a mounting side (3) and a rotation axis (z) having tool shank (1), an at least circumferentially one or more processing surfaces (5) comprising of the Tool shank (1) rotatably mitnehmbaren tool head (4) and at least one fastening means (6) for releasably securing the tool head (4) on the tool shank (1), characterized in that the tool shank (1) in the region of the machining side (2) has a cylindrical or approximately cylindrical, to the rotation axis (z) of the tool shank (1) arranged in alignment pin (7) on which the fastening means (6) is fastened or fastened, and which receives the tool head (4) with radial play, and that the tool head (4) is designed annular and in the attached state in at least one direction radially with respect to the axis of rotation (z) of the Werkzeugschaf tes (1) and relative to the pin (7) is displaceable. 2. Tool according to claim 1, characterized in that in the transition region between the tool shank (1) and pin (7) is arranged transversely to the axis of rotation (z) arranged contact surface (19) of the tool shank (1). 3. Tool according to claim 2, characterized in that between the tool head (4) and the contact surface (19) a driving ring (20) on the pin (7) by driving rotation and in a fixed state in at least one direction radially with respect to the axis of rotation ( z) of the tool shank (1) and is arranged displaceably relative to the pin (7). 4. Tool according to claim 3, characterized in that the tool head (4) in the first direction (x) relative to the driving ring (20) radially relative to the axis of rotation (z) is displaceable. 5. Tool according to one of claims 2 to 4, characterized in that in the contact surface (19) at least one to the rotation axis (z) perpendicular or approximately perpendicular recess (21) is arranged, through which at least one tool driver surface (22). is formed, to which a tool head or on the driving ring (20) arranged (first) tool driver (23) engages, whereby the tool shank (1) and the tool head or the driving ring (20) rotatably by entrainment are arranged to each other, and that Driving ring (20) along the recess (21) radially with respect to the rotation axis (z) is displaceable. 6. Tool according to one of claims 1 to 5, characterized in that in the tool head (4) at least one axis of rotation (z) substantially perpendicular recess (24) is arranged, formed by the at least one tool head driving surface (25) is, to which a on the tool shank or on a driving ring (20) arranged tool driver (26) engages, whereby the tool head (4) and tool shank or driving ring (20) are arranged rotationally fixed to each other, and that the tool head (4) along the recess (24) is displaceable radially with respect to the axis of rotation (z). 7. Tool according to claim 6, characterized in that the opposite tool head driving surfaces (25) of the recess (24) of the tool head (4) are inclined relative to each other, so that their distance to the tool shank out increases. 8. Tool according to one of claims 3 to 7, characterized in that the driving ring (20) has at least one franking (30), which in the region of the first and / or second tool head driver (23; 26) is arranged. 9. Tool according to one of claims 1 to 8, characterized by a radial mobility ensuring, in the region of the pin (7) on the tool head (4) effective axial gap (13). 10. Tool according to one of claims 1 to 9, characterized in that the fastening means (6) as a screw head (8), as a nut (10) or as a clamping or snap ring (5) is designed. 11. Tool according to one of claims 1 to 10, characterized in that in the tool shank (1) at least one liquid channel (17) is arranged for the transport of liquid, which extends substantially from the attachment side (3) to the processing side (2). extends, and in the region of the machining side (2) in at least one liquid outlet (18) opens, which is preferably arranged in the region of the pin (7). 12. Tool head (4) for a tool for machining holes or similar material recesses, in particular for a tool according to one of claims 1 to 11, with one or more at least circumferentially arranged processing surfaces (5), characterized by a in the axial direction ( z) extending central opening (31) in the tool head (4), whereby this on a pin (7) of the tool shank or the like can be plugged. 13. Tool head (4) according to claim 12, characterized in that the opening (31) comprises at least one conical surface (32). 14. Tool head (4) according to claim 13, characterized in that the inclination of the at least one conical surface (32) relative to the axis of rotation (z) is not greater than 5 ° and, preferably, a value between 0.1 ° and 2 ° Has. 15. Tool head (4) according to claim 12 or 13, characterized by a crank (33) of the opening (31). 16. Tool head (4) according to any one of claims 12 to 15, characterized by a in the region of the processing surface (5) arranged centering aid (37), which is preferably formed as a machining side arranged centering bevel (37 A). 17. Tool or tool head (4) according to one of claims 1 to 16, characterized in that the ratio length / diameter of the tool head (4) is smaller than 1, 5 and, preferably, in a range between 0.2 and 1, 5 lies. 18. Tool or tool head (4) according to any one of claims 1 to 17, characterized by at least one liquid channel (29) for transporting liquid along or transversely through the tool head (4).