Title of Invention

A TOOL FOR CHIP-BREAKING MACHINING

Abstract

A milling tool includes a number of peripheral recesses, each of which accommodates an insert-carrying, and a clamping wedge which is tightenable by of a clamping screw. The clamping wedge includes two separate contact surfaces. One of the contact surfaces presses the cartridge into its respective recess. The other contact surface presses the insert into its seat in the cartridge while simultaneously pressing the cartridge into the recess.

Full Text

A TOOL FOR CHIP-BREAKING MACHINING Technical Field of the Invention The present invention relates to a tool intended for chip-breaking machining, which tcol comprises a body that is rotatable around a central geometrical axis, said body having it peripheral envelope surface in which cue or several recesses being delimited by a bottom wall and leading and trailing walls is/axe provided, which diverge outwardly from the bottom wall, each one of said recesses separately having the purpose of accomodating on one hand a cartridge with a cutting insert being provided in a seat in said cartridge, and on the other hand a clamping wedge intended for fixing the cartridge, said wedge being tightenable by means of a clamping screw in engagement with a threaded hole that ends in the bottom wall in the body, the trailing wall of the recess ha\ ing a first serrations provided to cooperate with an analogous second serrations or a trailing side of the cartridge opposed to the cutting insert, while the leading wall of tin. recess is smooth in order to cooperate with an equally smooth leading surface of the clamping wedge, and a trailing bearing surface of the clamping wedge and a leading bearing surface of the cartridge both being smooth in order to, when in contact with each other, permit a substantially radial dislocation of the clamping wedge relative to the cartridge in connection with the fastening of the latter In particular - although not exclusively - the invention relates to milling tools, e.g., square shoulder facemills. facemills, slitting cutters or the like. Prior Art A tool realized in the shape of a milling cutter of the type as generaily described above, is previously known from SE 9103724-2. In this case, the individual cartridge can be introduced into the appurtenant recess from either the front or the back of the tool body the determination of the axial, position of the cartridge relative to the sucess being adjusted bv means of a radialy onented pin-provided on the lower side on the cathedic which pin is arranged to engage into a depression formed in the of the wall of the recess, said depression having a larger diameter than the pin Furthermore, each individual cutting insert is fastened on the appurtenant cartridge by means oi a headed screw that extends through a through-hole in the cutting insert and is tightened into a threaded hole in the cartridge The fact that the construction includes not only a clamping wedge for fixing only the cartridge per se, but also a particular clamping screw for fixing the cutting insert on the cartridge, in practice this means that the tolerance chain between on the one hand the tool body and its axis of rotation, and on the other hand each one of the numerous cutting inserts, becomes long Inter alia. this leads to a situation where the precision of the positioning of the cutting inserts relative to the tool body (which in practice should be less than 1/100 mm) may easily be lost or become unsatisfactory, e.g., when the cutting inserts are to be replaced or indexed, or when for any reason, the cartridge has to be dismounted and remounted. In addition thereto, precisely the work of fine-adjusting the cutting inserts and the appurtenant cartridges relative to the tool body is tedious and time-consuming: something that is particularly disturbing when the nulling tool is to operate at high speeds of rotation and/or in tough matenals, which give limited life of the cutting edges of the inserts and. thereby, necessitate frequent replacement or indexing of the cutting inserts. Objects and Characteristics of the Invention The present invention aims at eliminating the above mentioned inconveniences of previously known tools of the type in question and creating an improved tool, in particular a milling tool Thus, a primary object of the invention is to provide a tool with detachable cutting inserts which may be fixed in seats in appurtenant cartridges without other means than the clamping wedges that are used for the fixing of the cartridges ir the peripheral recesses of the tool body. A further object is to provide a tool in which the individual cartridge as well as the appurtenant cutting insert arc capable of with ease, taking up exactly defined operative positions relative to the tool body in connection with the mounting of. on one hand, the cartridge in the recess and, on the other hand, the cutting tasecrt in the cartridge seat Another object is to create a to with a good ability to withstand at least minor break-downs in connection with, e.g . instantaneous and abrupt impact and shock loads in pacticular. the cartridge sh.shall be Capable of resisting such loads without being seriously damaged or dislocated from its basic position. Still another object of the present invention is to provide a tool particularly intended for milling purposes, which may work at very high speeds of rotation e.g. up to the range of 20000 to 30000 rpm. One particular aspect of the invention aims at providing a tool whose cutting inserts are secured centrifugally in a reliable way, even when the tool is caused to rotate at very high speeds of rotation. According to the invention, at least the primary object is achieved by providing a clamping wedge with two separate contact surfaces. One of the clamping surfaces functions to press an insert-carrying cartridge into a respective recess of a tool body and the other contact surface functions to press the insert into its insert sea of the cartridge while also pressing the cartridge into its recess. Brief Description of the Appended Drawings : In the drawings : Fig.l is a perspective exploded view showing a part of a tool according to the invention, more specifically in the form of a milling tool, a number of cartridges and cutting inserts belonging to the tool being illustrated at a distance from the tool body, Fig.2 is a perspective view of an individual cutting insert which forms part of the tool, Fig.3 is a further perspective view showing an alternative embodiment of the cutting insert, Fig.4 is a partial, schematic side view showing a cartridge, a cutting insert and a clamping wedge in a first functional state, Fig.5 is a side view corresponding to Fig.4 showing said components in a second functional state, Fig.6 is a third side view showing a third functional state, Fig.7 to 9 are side views of the same type as in Fig.4 to 6, but showing an alternative embodiment of the cutting insert viz. the embodiment that is illustrated in Fig.3, and Fig. 10 is a simplified planar view of a portion of an alternative embodiment of the tool according to the invention, vis. In the form of a slitting cutter. Detailed Description of" Preferred Embodiments of the Invention In Fig. 1, reference numeral ] designates in general a body in the shape of a milling cutter head which is rotatable around a central geometrical axis (not shown). In the example, the body 1 is delimited by a peripheral, envelope-like surface 2 that extends between opposed gable surfaces 3, 4. of which the former is constituted by a front sidf. in whose proximity the cutting inserts of the tool are located, while the latter is constituted by a rear side, to which a rotatable spindle or the like(not shown) is connected in a suitable manner. Outwardly diverging recesses 5. which have the purpose of accomodating on the one hand a cartridge 6, 6a, and on the other hand al least one clamping wedge 7 are formed in the envelope surface 2. Each individual recess 5 (see also Fig. 4 to 6) is delimited by a leading wall 8. a trading wall 9 and a bottom wall generally designated 10. The clamping wedge 7 cooperates with, and is tightenable by, a screw 11 which is in engagement with a threaded hole 12 that leads to the bottom wall 10 of the recess 5. More specifically, the screw 11 is of the type that comprises both a right-hand thread and a left-hand thread, these threads being separated from each other via a waist porti :m. One of these threads engages with the hole 12 in the tool body, while the other thread engages with a threaded through-hole 13 in the clamping wedge 7. The two male threads on the screw 11 have a certain play relative to the female threads of the holes 12, 13. Thanks to the existence of double threads on the screws 11, it becomes possible to move the clamping wedge 7 in a way known per se that gives increased velocity relative to the body, e.g., with double velocity in comparison with one single thread in connection with a rotation of the screw in either direction of rotation. The trailing wall 9 of recess 5 has a first serrations generally designated 14 which is arranged to cooperate with an analogous, second serrations 15 on a trailing side of the cartridge 6. In this context it should be pointed out that the terms "leading" and "trailing" walls, respectively, relate to the direction of rotation of the ton! which l indicated by the arrow' A. Thus when seen in the direction of relation of the tool the serrations 1 5 are formed on that trailing side of the cartridge that is facing away from a leading side in which a seat 16 is provided for a cutting insert 17. The leading wall 8 of an individual recess 5 (see also Fig. - to 6) is (at least partly; smooth and suitably planar in order to cooperate with an equally smooth and planar leading surface 18 on the clamping wedge 7. A trailing bearing surface 19 on the clamping wedge 7 is equally smooth and planar in order to cooperate with a leading, planar and smooth bearing surface 20 on the cartridge 6. As a result of the fact that sad surfaces 8, 18, 19 and 20 are smooth, the clamping wedge may be moved without an obstacles substantially radially relative to the tool body and the cartridge in connection with the clamping ot the latter Although the serrations 14, 15 are of known type, which is an advantage, it deserves mentioning that the same are generally formed of ridges that are separated by intermediate grooves. As may be seen in Fig 1 in combination with, e g., Fig. 4, the individual toothings or serrations thus comprises a set of elongated, straight and into parallel ridges which may engage in the grooves of the other serrations. Advantageously, both the ridges and the grooves have a triangular cross-sectional shape, the free crests of the ridges being topped so that the ridges do not touch the bottoms in the cooperating grooves when the serrations are brought into engagemeni with each other. This implies that each individual ridge in one of the serrations is wedged very firmly between a pair of adjacent ndges in the other serrations In othe: terms, a plurality of wedge joints is obtained at the boundary between the cartridge and the tool body. In practice, the lop angle between the flank surfaces of the individual ridge (and the corresponding angle between the side surfaces of the individual groove: may amount to about 65°. Advantageously - however not necessarily - the serrations extend the whole way along the axial length of the recess 5. i.e., between the gable surfaces 3, 4. and the serrations 15 extend along the whole length of the cartridge 6. As far as the milling tool shown in the drawings has been described hereto, it is substantially known from SE 9103724 2 make sure, before the distinguishing features of the tool according to the invention are described more thoroughly, it should be pointed out that the two different embodiments of curling inserts that are shown in Fig. 2 and 3 are illustrated simantaneously in Fig. 1. More specifically, the cutting insert 17 according to Fig 2 is (shown coupled with a cartridge 6 which in a certain respect differs from the two cartridges 6a that accomodate a cutting insert 17' of the type shown in Fig. 3. In practice, only cartridges with cutting inserts of one and the same uniform type are usee on the milling tool, but due to space reasons it has been chosen to illustrate the two different rypes ol cutting inserts and cartridges in one and the same drawing figure. Reference is now made to Fig 2.4, 5 and 6, which illustrate the invention as it is applied with the cartridge 6 shown to the left in Fig 1. In this case, the cutting insert 17 is of a simple type, as far as it is delimited by substantially planar top and bottom sides 2.1, 22, and a number of oblique relief surfaces 23 Between the top side 21 and the individual relief surface 23 a cutting edge 24 is formed The seat 16 in the cartridge 6 has of course a shape that is suited to the shape of the cutting insert. Thus, the seat is delimited by a planar bottom surface 25 and two side surfaces 26 extending perpendicularly to each other, which are inclined relative to the bottom wail 25 at the same angle as the angle between the relief surfaces 23 of the cutting insert and the bottom side 22 It is characteristic for the present invention that the clamping wedge 7, besides an inner portion 7 on which the before-mentioned, trailing bearing surface 19 is formed, comprises an outer part 7" with a secondary bearing surface 27 which is dislocated backwards relative to the first-mentioned bearing surface 19. In other words, the secondary bearing surface 27 is situated behind an imaginary plane in the straight extension of the surface 19. Moreover, the leading bearing surface 20 on the cartridge: 6 is formed on an inner part 6" of the cartridge, being located radially inside the seat 16 The bearing surface 20 is inclined at a certain, restricted angle relative to the top surface 21 of the cutting insert and the bottom surface 25 of the seat, iespectively. In Fig. 6, according to which the cartridge us well as the cutting insert are shown in a fixed stale,  designates an angle between, on the one hand the leadinp wall 8 of the recess 5 and on the other hand the top surface 21 of the cutting insert. In this state, the bearing surface 20 is parallel to the wall 8, of which follows that the angle of obliquity between the bearing surface 20 and the bottom surface 25 of the seat is one and the same as the angls  According to the concrete practical example, this angle amounts to I2C. In practice, the angle a may vary, but should lie within the range 8 to 25°, suitably 10-20° and preferably 11-15°. The secondary abutment surface 27 on the clamping wedge 7 also extends at a certain restricted angle to the. trailing bearing surface 19, viz. at said angle a At its radial outer edge, the leading abutment surface 20 of the cartridge 6 transposes into an oblique chamfer surface 28. along which an inner end portion 29 of the clamping wedge may slide in connection with its introduction into the space between the cartridge and the leading wall 8 of the recess. Advantageously, this inner end portion 29 is also formed with a chamfer surface 30 that is inclined at an acute angle relative to the rear bearing surface 19 of the clamping wedge. In Fig. 4, the clamping wedge 7 is shown in a non-tightened state. A geometrical central line is designated B, which in the state according to Fig. 4 is common for the screw 11 and the two threaded holes 12, 13 in the tool body and the clamping wedge, respectively. In this state, the front surface 18 of the clamping wedge is somewhat inclined relative to the leading wall 8 of the recess, more specifically at an angle designated p. In practice, the angle (3 may amount to about 3° The function of the invention should be evident from a comparison between Fig. 4, 5 and 6. In the state as shown in Fig 4, the cutting insert 7 is separated from the carindr..-6. and the cartridge is inserted into the recess 5 without being influenced by the clamping wedge 7, which however, in its turn, is mounted on the screw 11 and kept fastened relative to the body by the fact that the inner thread of the screw is provisionally tightened in the hole 12. By lightening the screw 1 1 (which may be dons from the outside of the clamping wedge by means of. e.p . a hexagon key,), in a first step the clamping wedge may be moved to the position that show in fig a here the clamping wedge has been pulled in so fax that the trailing bearing surface 19 of the clamping wedge has abutted tht leading bearing surface 20 of the cartridge, after The two chamfer surfaces 28, 30 having slid along each other and passed each other. In connection with the moment when the chamfer surface 30 r sses the chamfer surface 28, a wedging effect is achieved that brings the serration 15 of the cartridge into a distinct engagement with the serration 14 of the tool body. At the same time, the clamping wedge is brought to turn anticlockwise around the fulcrum that is created by the linear edge 31 between the wall 8 and a vaulted surface 32 between the recess 5 and the envelope surface 2 of the tool body. More specifically, the clamping wedge is forced to turn m such a way that its leading surface 18 is laid with complete surface contact agamsi the leading wall 8 of the recess. It is true that this requires that the geometrical central axis for the Threadcd hole 13 in the clamping wedge, said axis being designated C in Fig 5, need be turned by 0 relative to the central axis B for the threaded hole 12, but in practice this angular change may very well be accomodated by the previously mentioned play between the male threads of the screw 11 and the female threads of the holes 12, 13. When the clamping wedge 7 has taken its position as shown in Fig. 5. the cartridge per se is fixed in a reliable way by the wedge joint between the serrations 14, 15. However the cutting insert 17 is still freely movable into and out of the seat 16. in that the distance between file secondary bearing surface 27 and the seat bottom 25 is somewhat larger than the thickness of the cutting insert. In practice, this dimensional difference, which in Fig. 5 is designated D, amounts to 0,2 to 0,4 mm. depending on the overall geometry of the construction. In a concluding, third step that is shown in Fig 6, the screw 11 and the clamping wedge 7 are finally tightened. Thereby, the secondary bearing surface 27 on the clamping wedge will be gradually moved radially inwards relative to the cutting insert, in arder o be finally pressed and wedged against the top side 21 ot the cutting insert. In this state the clamping wedge thus fixes not only the cartridge 6 but also the cutting insert ;" In connection with a change or indexing of the cutting insert 17, this may be quickly and easily detached from the cartridge by the simple measure of screwing out the screw and the clamping wedge a bit, to the position which is shown in Fig. 5 and in which the secondary bearing surface 27 is distanced from the top side of the cutting insert. In this state, the cartridge 6 is still reliably fixed in the appurtenant recess; more specifically ay the fact that the clamping wedge still presses the cartridge by a force resultant R (see Fig. 6) that hits the serration 14 at a level outside its innermost ridge. Being able to utilize one and the same means, namely the clamping wedge, for fixing both the cartridge and the cutting insert, without any necessity of detaching and remounting the cartridge in connection with the removal of the cutting insert from the seat, is a considerable advantage in connection with the practical use of the tool, on the one hand, in view of the fact that the risk of tolerance errors is reduced, and on the oner hand in view of the fact that the changing and indexing of the cutting insert are simplified. Another advantage of the invention is that the point of contact between the-bearing surfaces 19, 20 of the clamping wedge and the cartridge form an abutment that is deeply located in the appurtenant recess, which abutment effectively counterads possible tendencies of the cartridge and the cutting insert to tip in connection with sttuatms when the cutting insert is exposed to large tangential forces. The contact place deeply located in the recess between the bearing surfaces 19, 20 also brings about possibilities to shape the clamping wedge with a limited radial height. In other word;, the outwardly facing surface of the clamping wedge may be placed relatively deeply within the recess in relation to the operative cutting edge of the cutting insert, while attaining a large space for chip removal adjacent to the top side of the cutting insert in this context it should also be mentioned that the absence of clamping screws for the cutting insert improves the conditions for using cutting inserts of hard and brittle materials, such as ceramics. In practice, the tool construction illustrated in Fig. 1 permits the bodv 1. as such, to be made of aluminium or another light material, while the cartridges and clamping wedpes may be made of steel or similar material By giving the tool bodv which to voiuminials in comparison to the cartridges and the clamping wedges, a low weight, the total we the of the tool can be radicaly reduced; something that on one hand makes possible shorter acceleration and retardation times in connection with frequently repeated Starting and stopping operations, and on the other hand makes possible an oprative running with extremely high speeds of rotation, eg , in the range of 20 000 to 30 000 rj>m. In practice, the embodiment described in connection with Fig. 2, 4, 5 and 6 with a cutting insert with planar top and bottom sides, is suitable for running at medium high speeds of rotation, e.g., up to the range 10 000 to 20 000 rpm, but less so for extremely high speeds of rotation in fig 3 and 7 to 9, and in the right part of Fig. I. an embodiment of the invention is shown that may be advantageously used when it is desired to work with extra-ordinary high rotation speeds. As maybe seen in Fig. 3, this embodiment comprises a cutting insert 17', in whose top side 21 is formed a first depression 31 which has the shape oi i substantially V-shaped groove that extends between two opposed edges of the insert More specifically, the V-groove 53 is delimited by two planar side surfaces 33' In Fig 3 may also be seen how the V-groove 33 extends at a certain acute angle relative to two opposed cutting edges (for the simple reason that the milling tool is foreseen for squar; shoulder facemling and has an overall geometry adapted for this purpose) Furthermore, a female recess generally designated 34 ends in the bottom surface 17th in practice, this recess may be comparatively shallow and have a rotation-symmetnea! shape, e.g., the basic shape of a frustum of a cone. As may be seen in the right part of Fig. 1 as well as in Fig 7 to 9, a male means 3S is provided on the bottom side 25 of the cuttuig insert seat, for engagement with the female recess 34 in the cutting insert. In practice, the male means may have the same basic shape as the recess 34, but on all sides being smaller than the latter, so that the external side of the male means normally never comes in touch with the internal side of the female recess In Fig 7 to 9 may be seen how the secondary bearing surface 27 of the clmping wedge 7 in this case is provided on a special heel 36 on the claimping nedge- more specianth on this heel 36 is provided a sr-face designated 37, which in turn extends at a certam, moderate angle to the trailing. memory bearing surface 19 of the clamping wedge. The angle designated in Fig between the individual side surface 33 in the. V-groove land the top surface 2 '., may amount to about 8° The secondly bearing sunace 2.1 is [inclined relative to surface 37 by the same angle k, i.e., by 8°. Of course, the angle may deviate from exactly 8°. but in practice it should lie within the range of 6 to 120 When the damping wedge 7 is f.ually tightened in the position according, to fig 9, the the protrusion 35 and the heel 36 secure the cutting insert from the risk of being flung radially outwards from the seat bv the centrifugal force. In its fixed position according to fig 9, the cutting insert is held clamped by means of the clamping wedge 7 according to previously generally described ways, although with the difference that the male bee! 36 mechanically engages into the female depression in the form of the V-groove 33 However, in this state the protrusion is normally inactive, in that the same lacks vonlacl with the internal side of the recess 34 Only in an extreme case, would the protrusion 35 become active. we it the cutting insert during work at very high speeds of lotanon would be submitted to shock impacts and/'or an extra-ordinarily large centrifugal forces In these cases, the protnision guarantees that the cutting insert dot-not leave the seal, even if the side surface in question in the V-groovc would tend to slide relative to the secondary bearing surface 27 In the embodiment with a centritugally secured cutting insert according to fig 7 to 9 the cutting insen must be distanced by a considerable distance from the bottom surface of the seat in connection with replacing or indexing cutting inserts This means that also the clamping wedge 7 has to be removed from the proximity of the cutting insert For this leason, the clamping wedge 7 is provided with the support of a second clamping wedge 38. which is placed in tlie axial extension ot the first-mentioned clamping weatge and which has the single purpose of fixing the cartridge Tins second clamping wedgt 38 is tightcnable by inram ot a second double-threaded screw 39 In their active final Tightened states, the two clamping wedges 380c'opcrate to jointely clamp the cartage whereas, however. only the ampiny wedge simultancosly also claimps the cuttings inserted the seat of the cartege When the culling insert is to be removed from the cartridge, the first clamping wedge rnay be removed or screwed out to suck an extent that the cutting insert may be removed from the seat, without the cartridge being displaced from its given adjusted position, in that the second clamping wedge.38 then still keeps the serrations 14, 15 in unaltered engagement with each other According to a preferred embodiment of the invention, the bottom wall 10 of the individual recess 5 is divided into at least two part walls 10', 10", which arc located a different radial distances from the rotation axis of the tool body, and which are separated by a fust abutment surface 40 facing the cutting insert. This abutment surface 40 extends at an angle, suitably perpendicularly, to the serrations 14 in the trailing wall of the recess, and has the purpose of cooperating with an analogous second abutment wall 41 on the cartridge 6a It also extends perpendicularly to the part wall 10' This second abutment surface 41 extends correspondingly, suitably perpendicularly to the solutions 15 of the cartridge (in fact, perpendicularly to the axial extension of the rides and grooves). When the cartridge is mounted into the recess, its location can be determined, in a simple manner, in a predetermined basic position merely by the simple measure ol banging the serrations 14, 15 to slide along each other till the abutment surface 41 abuts the abutment surface 40. Since both the abutment surface 40 on the tool body (also in this case the latter is mails of aluminum) and the abutment surface 4i on the cartridge (usually of steel), may be made with high accuracy, the cartridge may in a simple manner be mounted into an exactly defined basic adjustment position, that is easily repcatable and uniform for al. cartridges and recesses on the tool. The tool may be provided wjth means tor enabling a fine adjustment of the cartridge relative to the body. In Fig. 1 such a means is exemplified in the form ol a separate ks 42 that is msertable into a through, cylindrical bore 43 in the cartridge. The key 42 comprises a cylindrically shaped shaft 44 which at a free end transposes info ar, eccentric body 45 that shall be brought into engagement with an elongated depression 46 in the bottom part wall 10". Therefore, by turnms the key. fine area movements relative to the tool body may be conferred to the cartridge, whilele the two clamping wedges are moderately tightened. The ability to make fine-adjustments to the position of the cartridge, e.g., to thousandths or hundredths of a millimeter, is important on one hand in such cases when tolerance deviations occur in connection with manufacture, and on the other hand in such cases when the cartridge unexpectadly would have been dislocated from its basic adjustement position, e.g., due to shock impacts For the sake of completeness, it should be mentioned that the part wall 10" radially protruding relative to the bottom pan wall 10'. in its turn transposes into an angularly broken part wall 10; in which a threaded hole 47 for the clamping screw 39 ends. The part wall 10'" extends perpendicularly to the leading wall 8 of the recess. at the same tunc as the part wall 10" also extends perpendicularly to the trailing wall provided with the serrations 14, which wall extends at an acute angle (e.g.. within the range is to 350 C ro the leading wall 8. In fig. 10 is indicated schematically how the invention may advantageously also be applied on slitting cutters of the type that comprises an extremely thin, plate-shaped tool body 1. hi this case, one single clamping wedge 7 may simultaneously hold a cartridge 6 as well as a cutting insert 17, it being possible according to the previously described manner to clamp and maintain the cartridge in its adjusted position also when the cutting insert is to be replaced or indexed Feasible Modifications of the Invention the invention is not limned sofety to the embodiments as described and shown in the drawings. Thus, the cutting inserts and the appurtenant seats in the cartridge may have other arbitrary basic shapes than mst square or penerall'V quadrilateral I he cutting, inserts may. for instance have a true a rsana pugnasl shape Althose the invention has been exemplified specilicalv ir, connection with the the also be applied to other types of rotating tools for chip breaking machining of the kind that makes use of cartridges witth detachable cutting inserts. WE CLAIM 1. A tool intended for chip-breaking machining comprising a body (1) that is rotatable around a central geometrical axis, said body having a peripheral envelope surface (2) in which is/are provided one or several recesses (5) being delimited by a bottom wall (10) and leading and trailing walls (8,9), each one of which recesses separately having the purpose of accommodating on the one hand a cartridge (6) with a cutting insert (17) being provided in a seat (16) in said cartridge, and on the other hand a clamping wedge (7) intended for fixing the cartridge, said wedge being tightenable by means of a clamping screw (11) in engagement with a threaded hole (12) that ends in the bottom wall in the body (1), the leading wall (8) of the recess being smooth in order to cooperate with an equally smooth leading surface (18) of the clamping wedge (7), and a trailing bearing surface (19)of the clamping wedge and a leading bearing surface (20) of the cartridge (6) both being smooth in order to, when in contact with each other, permit a substantially radial dislocation of the clamping wedge relative to the cartridge in connection with the fastening of the latter, said leading and trailing surfaces (18,19) of the clamping wedge (7) being parallel to each other, the clamping wedge (7) besides an inner part (70, on which said trailing bearing surface (19) is provided, comprising an outer part (7") with a secondary bearing surface (19), the inner part (7) of the clamping wedge being insertable into the space between the bearing surface (20) of the cartridge and the leading wall (8) of the recess by tightening of the clamping screw (11), in order to be capable of taking on one hand a provisional outer position in which the cartridge (6) is fixed, without the secondary bearing surface (27) of the clamping wedge being pressed against the cutting insert (17), and on the other hand an inner, finally tightened end position in which the secondary bearing surface (27) of the clamping wedge is pressed against the top surface (21) of the cutting insert, while fixing it into the appurtenant seat (16), characterized in that said leading and trailing walls (8,9) diverge outwardly from the bottom wall (10), in that the trailing wall (9) of the recess (5) has first serrations (14) provided to cooperate with analogous second serrations (15) on a trailing side of the cartridge (6) opposed to the cutting insert, in that the leading bearing surface (2) on the cartridge is provided on an inner part of the cartridge located inside the seat (16) and its cutting insert (17) and extends parallel to the leading wall (8) of said recess when said first and second serrations (14,15) are fixedly interengaged, and in that the cartridge (6) is fixed in said outer provisional position by said first and second serrations (14,15) engaging into each other. 2. Tool as claimed in claim 1, wherein the leading bearing surface (20) of the cartridge transposes into an oblique chamfer surface (28) along which an inner end portion (29) adjacent to the inner bearing surface (19) of the clamping wedge is slidable in connection with the introduction of the clamping wedge into said space between the cartridge (6) and the leading wall (8) of the recess (5). 3. Tool as claimed in claim 2, wherein also the inner end edge portion (29) of the clamping wedge is formed with a chamfer surface (30) that is oblique relative to said inner bearing surface (19). 4. Tool as claimed in any of the preceding claims, wherein the secondary bearing surface (27) of the clamping wedge is oblique relative to the inner bearing surface (19) at an angle within the range 8 to 25°, suitably 10 to 20° and preferably 11 to 15°. 5. Tool as claimed in any of the preceding claims, wherein the secondary bearing surface (27) of the clamping wedge (7) is provided on a heel (36) protruding from the trailing side of the outer part (7") of the clamping wedge and cooperates with one of two side surfaces (33') in a groove (33) with a V-shaped cross-section in the top surface (21) of the cutting insert. 6. Tool as claimed in any of the preceding claims, wherein the clamping screw (11) comprises a right-hand thread as well as a left-hand thread separated from the former, of which threads one is in engagement with a threaded hole (13) in the clamping wedge (7) and the other with the threaded hole (12) in the tool body (1), the two male threads having a certain relative play relative to the cooperating female threads, and that the clamping wedge (7), when tightening the clamping screw (11), is linearly moveable along the geometrical central axis (B) of the threaded hole (12) in the tool body up to a certain point where the trailing inner bearing surface (19) of the clamping wedge comes in contact with the leading bearing surface (20) of the cartridge, whereby the clamping wedge is forced to turn inwards/forwards under a pressing of the leading surface (18) of the clamping wedge into a complete surface contact with the leading wall (8) of the recess (5), said turning movements of the clamping wedge being accommodated by said thread play, and the inner part (70 of the clamping wedge being axially movable from said contact point to its inner, cutting insert-fixing end position thanks to the parallelity between the inner bearing surface (20) of the cartridge and the leading wall (8) of the recess. 7. Tool as claimed in any of the preceding claims, wherein each one of said serrations (14,15) comprises a set of elongated straight and inter-parallel ridges that are separated by intermediate grooves, the ridges as well as the grooves having a triangular cross-sectional shape and the free crests of the ridges being topped so that the ridges do not reach the bottoms in the cooperating grooves when the serrations are brought into engagement with each other. 8. Tool as claimed in any of the preceding claims, wherein the bottom wall (10) of the individual recess (5) is divided into at least two part walls (1010") at different radial distances from the axis of rotation, which walls are separated by a first abutment surface (40) facing the cutting insert (17), said abutment surface extending at an angle to the serration (14) in the trailing wall (9) of the recess and having the purpose of cooperating with an analogous, second abutment surface (41) on the cartridge (6), more specifically in order to hold the cartridge and the appurtenant cutting insert in an exactly defined basic adjustment position relative to the tool body (1). 9. Tool as claimed in any of the preceding claims, wherein on the top side (21) of the individual cutting insert (17) a first depression (33) for receiving a heel (36) of the clamping wedge carrying the secondary bearing surface (27) is provided, and that in the bottom side (22) of the cutting insert a female recess (34) and/or a male means for cooperation with a suitable male means and/or a female recess in the bottom surface (25) of the seat (16) is provided, all this in order to secure centrifugally the cutting insert in the seat. A milling tool includes a number of peripheral recesses, each of which accommodates an insert-carrying, and a clamping wedge which is tightenable by of a clamping screw. The clamping wedge includes two separate contact surfaces. One of the contact surfaces presses the cartridge into its respective recess. The other contact surface presses the insert into its seat in the cartridge while simultaneously pressing the cartridge into the recess.

Documents:

IN-PCT-2001-393-KOL-(02-04-2012)-PETITION UNDER RULE 138.pdf

IN-PCT-2001-393-KOL-(27-04-2012)-FORM-27.pdf

in-pct-2001-393-kol-granted-abstract.pdf

in-pct-2001-393-kol-granted-assignment.pdf

in-pct-2001-393-kol-granted-claims.pdf

in-pct-2001-393-kol-granted-correspondence.pdf

in-pct-2001-393-kol-granted-description (complete).pdf

in-pct-2001-393-kol-granted-drawings.pdf

in-pct-2001-393-kol-granted-examination report.pdf

in-pct-2001-393-kol-granted-form 1.pdf

in-pct-2001-393-kol-granted-form 18.pdf

in-pct-2001-393-kol-granted-form 2.pdf

in-pct-2001-393-kol-granted-form 3.pdf

in-pct-2001-393-kol-granted-form 5.pdf

in-pct-2001-393-kol-granted-gpa.pdf

in-pct-2001-393-kol-granted-pa.pdf

in-pct-2001-393-kol-granted-priority document.pdf

in-pct-2001-393-kol-granted-reply to examination report.pdf

in-pct-2001-393-kol-granted-specification.pdf