WO2008029005A1

WO2008029005A1 - Circular cutting tool with segments and production method thereof

Info

Publication number: WO2008029005A1
Application number: PCT/FR2007/001323
Authority: WO
Inventors: Hervé DEFRENEIX
Original assignee: Amvdiam
Priority date: 2006-09-08
Filing date: 2007-07-31
Publication date: 2008-03-13
Also published as: FR2905617A1; FR2905617B1

Abstract

The invention relates to a circular cutting tool (100') consisting of a supporting disc (110') and a plurality of circular segments (120') which are provided with cutting teeth and mounted to the periphery of the supporting disc. According to the invention, the supporting disc has a rib- and groove-free smooth outer section to which the rib- and groove-free smooth inner longitudinal section of each segment is secured by means of brazing, welding or bonding. In addition, the smooth outer section of the supporting disc and the circular segments are provided locally with male (111') and female (121') elements which, without being secured by means of brazing, welding or bonding, co-operate mechanically with one another in order to take up the orthoradial shear stresses to which the cutting tool is subjected. The invention also relates to a method for producing one such tool.

Description

SEGMENT CIRCULAR CUTTING TOOL AND PROCESS FOR MANUFACTURING A

TEL TOOL

TECHNICAL FIELD TO WHICH THE INVENTION RELATES The present invention relates to a circular cutting tool which comprises a support disc and a plurality of circular segments provided with a cutting toothing, attached to the periphery of the support disc.

It also relates to a method of manufacturing such a tool. The invention finds a particularly advantageous application in the production of an industrial tool adapted to cut some complex products such as sections with large sections or stainless steel products as well as all kinds of materials such as steel, copper, and the like. aluminum, paper, cardboard and plastics.

BACKGROUND ART Currently in segmental circular cutting tools already known, the support disc is made of base steel chosen from alloy or non-alloy steels, cold-working tool steels and hot-tool tool steels. , and only the circular segments are made of quick tool steel which, compared to alloy or non-alloy steels, cold tool steels and hot-tool steels, has hardness and resistance after quenching. higher at high temperatures up to about 600 ° C.

According to the definition given in EN ISO 4957 of December 1999 in Chapter 3, paragraph 3.3.3, the fast tool steel is mainly used for machining and forming and, compared to other steels such as alloy steels or non-alloyed, tool steels for cold work or for hot work, it has, by its chemical composition, the highest hardness and resistance after quenching at high temperature up to about 600 ⁰ C.

It is in particular a steel strongly alloyed in tungsten, cobalt, molybdenum and vanadium. For example a fast tool steel may comprise a mass share of all three elements that are tungsten, cobalt and molybdenum, greater than 5%. Fast tool steel and carbide are very expensive materials that have high performance sought for the realization of the active cutting parts of industrial tools.

Generally, in segment tools already known, such as those described for example in GB 977 837, DE 1 902 901 and DE 36 02

904, the support disc carries on its periphery a rib on which is encased each circular segment. For this, each circular segment has in its inner longitudinal slot an interlocking groove. In addition, the circular segments are secured to each other and to the support disk using rivets.

The segment tools have a manufacturing overhead due to the massiveness of the segments relative to the useful part of the cut and the mechanical assembly of the segments with the support disc of the tools.

The realization of these tools is complex and requires mastering multiple steps such as milling, heat treatment, annealing, grinding, and riveting.

Furthermore, DE 27 30 912 and DE 91 05 709 disclose equivalent cutting blades which comprise a disc provided on its periphery with teeth whose ends bear cutting segments. Each segment comprises, on its outer edge, a cutting portion and, on its inner edge, a mounting foot fitted into a groove provided in the outer edge of the support disk at the end of each tooth.

According to DE 27 30 912, the mounting foot covers most of the inner edge of each segment and each groove extends in correspondence over most of the length of the outer edge of each tooth of the carrier disk. It is furthermore provided to reinforce the mechanical fastening of the foot of each segment in the corresponding groove of the disk by gluing or by removal.

According to DE 91 05 709, the mounting foot forms a rib along the entire length of the inner edge of each segment, this rib is nested in a groove which extends over the entire length of the outer edge of each tooth of the disc. . Here, there is no provision for a bonding, a withdrawal or a weld, the joining of the foot of each segment in each groove of the disc being made exclusively mechanically. The realization of these tools is also complex and requires mastering multiple steps such as milling, heat treatment, annealing, and rectification.

Finally, US Pat. No. 4,570,517 discloses another type of cutting blade which does not comprise a central disk bearing around its cutting edges but which is produced by the mechanical assembly of several disk segments each integrating on its outer edge a cutting teeth.

OBJECT OF THE INVENTION Compared to the prior art, the present invention proposes a new high-performance cutting tool, particularly suitable for cutting certain complex products such as stainless steel products or sections with large sections and whose process manufacturing is optimized so that the cost price of such a tool is lowered. More particularly, according to the invention, there is provided a circular cutting tool as defined in the introduction, wherein the support disc has a smooth outer edge, free of groove or rib, on which is secured by brazing, welding or gluing the wafer longitudinal internal smooth, groove-free or rib-free, of each circular segment, and in which it is provided locally on said smooth outer edge of the support disk and on said circular segments, male and female elements cooperating mechanically with each other, without being joined together by brazing, welding or gluing, to take orthoradial shear forces experienced by the cutting tool. Here, according to the invention, the joining between the circular segments and the support disc is essentially achieved by brazing, welding or gluing of slices or smooth surfaces contiguous to each other, the mechanical male / female interaction provided between the segments. and the disk intervening only in the background, punctually on said smooth edge of the support disk, to reinforce said joining by brazing, welding or gluing and to prevent it from deteriorating due to the orthoradial shear forces experienced by the cutting tool.

Other non-limiting and advantageous features of the cutting tool according to the invention are the following: - Said male and female elements are interlocking means nested in each other;

- The male elements are tenons and the female elements are notches having a substantially rectangular shape; - The back of the tenons and the bottom of the associated notches follow an inclined orientation relative to the edge of the support disc;

- The male elements are tenons and the female elements are notches having a shape substantially dovetail;

- The male and female elements are complementary recesses respectively formed by the outer edge of the support disk and the inner longitudinal edge of each circular segment, adapted to bear against each other;

the peripheral outer edge of the support disk is formed of a succession of circular arcs off-center with respect to the center of the support disk, these arcs of circle being connected to one another by said recesses;

each circular segment comprises one of said male or female elements placed in a median portion of its portion secured to said support disk;

each circular segment comprises one of said male or female elements placed at each of its two ends;

. - Each circular segment has a half-notch at each of its two ends, the meeting of two half-notches circular segments juxtaposed forming a notch receiving a stud provided projecting from the outer edge of the support disc; - The support disc comprises projecting on its outer edge a plurality of studs distributed around its periphery, engaged in notches provided in correspondence on an edge of said circular segments;

said tenons come to form with the support disk to form a single piece; the end lateral edges of the juxtaposed circular segments are placed at a distance from one another so as to form a slot which is extended in the support disk;

the bottom of each slot provided in the support disc forms a circular opening; the edges of said lateral end edges of the circular segments are chamfered;

said slots separating the juxtaposed circular segments extend along radii of the support disc; said slots separating the juxtaposed circular segments extend in a direction inclined with respect to the radial direction of the support disk;

- The inclination of said slots is of the order of 15 ° relative to the spokes of the support disk;

the support disc is made of a base steel chosen from alloy or non-alloy steels, cold working tool steels and hot-working tool steels and circular segments are made of high-speed tool steel which, as compared with alloy or non-alloy steels, cold tool steels and hot-tool steels, has a higher hardness and resistance after quenching at high temperatures up to about 600 ^° C .;

the circular segments are made of a fast tool steel chosen from among the steels ABC3, M2, M35, M42, ASP2060 and M51;

- Each slot separating two adjacent circular segments extends along a line forming a recess with two end portions and a transverse central portion establishing the junction between the two end portions;

- said central portion of each slot connects to the two end portions by bends with inverted curvatures;

said central portion of each slot extends over a concentric circle portion at the peripheral edge of the support disc;

- At least one of the end portions of each slot which opens on the toothing of the tool extends in a direction inclined relative to the radial direction of the support disk;

the two end portions of each slot are parallel and extend in a direction inclined with respect to the radial direction of the support disk;

the inclination of each end portion of each slot is of the order of 15 ° with respect to the spokes of the support disk;

the circular segments are two by two linked together; - The connection between two circular segments is achieved by brazing, welding or gluing concentrically to a portion of said slot separating said segments; and

said portion of each slot surrounded by said connection is said central portion of the slot extending along a portion of a circle.

The invention also relates to a method of manufacturing a cutting tool as mentioned above, in which are cut in heat-treated steel plates circular segments comprising on a smooth longitudinal inner edge at least one male or female element, is cut in a steel plate a support disc with protruding on its periphery male or female elements, is reported on the periphery of the support disc said circular segments so that said male and female elements cooperate mechanically with each other, and joining by brazing, welding or gluing the smooth inner longitudinal edge of said circular segments to the smooth outer edge of the support disk by avoiding securing said male and female elements cooperating with each other.

DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT The following description with reference to the accompanying drawings, given by way of non-limiting examples, will make it clear what the invention consists of and how it can be implemented.

In the accompanying drawings:

- Figure 1 is a schematic front view of a first embodiment of a circular cutting tool according to the invention;

FIG. 2 is an exploded view of construction of the tool of FIG. 1; FIG. 3 is a diagrammatic front view of a second embodiment of a circular cutting tool according to the invention;

FIG. 4 is a view of detail B of FIG. 3;

FIG. 5 is a detail view A of FIG. 3;

FIG. 6 is a diagrammatic front view of a third embodiment of a circular cutting tool according to the invention;

FIG. 7 is a view of detail A of FIG.

FIG. 8 is a diagrammatic front view of a fourth embodiment of a circular cutting tool according to the invention;

FIG. 9 is a view of detail A of FIG. 8; - Figure 10 is a schematic front view of a fifth embodiment of a circular cutting tool according to the invention;

FIG. 11 is a view of detail A of FIG. 11;

FIG. 12 is a diagrammatic front view of a sixth embodiment of a circular cutting tool according to the invention, and

FIG. 13 is a view of detail A of FIG. 12.

FIGS. 1, 3, 6, 8, 10 and 12 show six embodiments of a circular cutting tool 100; 100 '; 100 "; 100" "100" "100" "advantageously used in the industry to cut all kinds of materials such as steel, stainless steel, copper and aluminum, paper, cardboard and plastics, especially large sections.

This circular cutting tool 100; 100 '; 100 "; 100" "100" "; 100" "has in its center an orifice 112; 112 '; 112"; 112 "; 112" "; 112" "" for mounting it on a drive shaft in rotation (not shown). 11 is bordered here over its entire periphery of a cutting teeth which can cut the material to cut by tearing.

This circular cutting tool 100; 100 '; 100 ", 100", 100 ", 100" "has a diameter that can vary in a range from 200 to 2200 mm.

The circular cutting tool 100; 100 '; 100 "; 100"; 100 "" 100 "" shown in FIGS. 1, 3, 6, 8, 10, 12 and 13, comprises a support disc 110; 110 '; 110 "; 110'"; 110 110 "" and a plurality of circular segments 120, 120 ", 120", 120 ", 120" ", 120" "attached to the periphery of the carrier disk 110; 110"; 110 "; 110 "" 110 "".

The circular segments 120, 120 ', 120 ", 120", 120 "" 120 "" have on their outer longitudinal edge a cutting toothing 120B, 120B, 120B, 120B, 120 ". "B; 120 '""B. The inner longitudinal edge 120A, 120A, 120A, 120A, 120A, 120A, each circular segment 120, 120, 120, 120, 120, 120 """forms a smooth slice, i.e. it is free of groove or rib. Advantageously, the support disk 110; 110 '; 110 ";110"; 110 ""; 110 ^"1" is carried out in a basic said steel steel selected from alloy or non-alloy steels, cold work tool steels and tool steels for hot working, and circular segments 120; 120 '; 120 "120""120""120""bearing cutting teeth are made of quick tool steel. Tool steels are defined in particular in Chapter 3 of EN ISO 4957 of December 1999.

According to this standard, tool steels are special steels suitable for work or material processing, handling and measuring of workpieces, which must be of high hardness and wear-resistant. and / or tenacious. Alloyed or non-alloy cold tool steels are intended for applications in which the surface temperature is generally less than 200 ⁰ C and hot working tool steels are alloy steels for applications in which the temperature of surface is generally greater than 200 ⁰ C without exceeding 500 ⁰ C but the fast tool steels are superior to the previous ones because they have, by their chemical composition, hardness and resistance after the highest tempering at high temperature up to at about 600 ^° C.

Alloyed or unalloyed steels are defined in ISO 4948-1. According to the invention, the support disk 110; 110 '; 110'; 110 ''; 110 ''; 110 '' 'can be made of a low-grade steel such as a non-alloyed chromium steel, even of iron, because it does not participate in cutting while the circular segments 120, 120 ', 120 ", 120" "120" "120" "carrying the cutting teeth, form the active cutting parts made of a noble steel, fast tool steel.

This considerably reduces the manufacturing cost of the cutting tool.

According to an advantageous characteristic, it is possible, for example, to provide that the base steel which constitutes the support surface 110, 110 ', 110' ', 110' '', 110 '' '' has a mass share of 1 set of three elements: tungsten, cobalt and molybdenum, strictly less than 5% and said fast tool steel constituting the circular segments

120, 120 ', 120' ', 120' ', 120' ', 120' '' 'have a mass share of all three elements: tungsten, cobalt and molybdenum, greater than or equal to 5%.

The support disk 110; 110 ^! 110 "110" ^! 110 "" 110 "" can be made in the following steels: X75CR1, 80CRV2, and 50CV4. In addition, the fast tool steel which constitutes said circular segments 120, 120 ', 120 ", 120""120""120""can be obtained traditionally by casting or by sintering (metallurgical method of powders).

Advantageously, when it is obtained from sintered powders, the fast tool steel used has a thinner structure and therefore a higher resistance to wear at high temperature.

The rapid tool steel which constitutes said circular segments 120, 120 ', 120 ", 120" "120" "120" "advantageously has a mass share of all three elements which are tungsten, cobalt and molybdenum between 5 and 25%.

Among these fast steels, one can use for example the steel M2, M42, M35, but also fast steels such as steel ABC3 and steel ASP2060 and M51.

According to an essential characteristic of the circular cutting tool 100; 100 ', 100 ", 100", 100 ", 100, said circular segments

120, 120 ', 120' ', 120' '', 120 '' ', 120' '' 'are joined by brazing, welding or gluing to the carrier disc 110; 110'; 110 '; 110' '; 110' '; ". For this, the inner longitudinal edge 120A, 120A, 120A, 120A, 120A, 120A, A of each circular segment 120, 120, 120 ", 120", 120 ". "120" ", which forms a smooth inner wafer, is welded, brazed or glued to the smooth outer peripheral wafer of the carrier disk 110; 110 ', 110 ", 110", 110 "" along a line S1 (see Figures 11 and 13). In addition, the support disk 110; 110 ', 110 ", 110", 110 ", 110" "projecting from its outer peripheral edge 113; 113"; 113 ";" "smoothing a plurality of male members 111; 111'; 111 ", 111" "111" ", distributed around its perimeter, which mechanically cooperate with female elements 121; 121 '; 121"; 121 "" 121 ""; correspondence on an edge of said circular segments 120; 120 '; 120 "; 120'"; 120 ""; 120 '"";

The outer peripheral edge of the support disk 110; 110 '; 110 "; 110" "110" "; 110" "is smooth, that is to say free of any ribs or grooves, and occasionally bears protruding said male elements 111; 111 '; 111 "; 111" "111" ";

According to the embodiments of the invention shown in FIGS. 1 to 11, said male and female elements are interlocking means nested or engaged in each other. These are pins 111, 111 '111'"111""provided on the periphery of the support disc 1 10; 1 10 '; 1 10 "; 1 1 0 '"; 1 "" cooperating with notches 121, 121 ', 121 ", 121""121""provided on the circular segments 120, 120', 120", 120 "" 120 "".

The tenons 11 1; 111 '; 11 "; 111'"; 111 "" which cooperate with the notches 121; 121 '; 121 "; 121" "121" "advantageously make it possible to take up the orthoradial shearing forces experienced by the cutting tool 100; 100'; 100"; 100 "100" "during cutting, which preserves the connection by brazing, welding or bonding occurring between the support disk and said segments.

According to the embodiment of the invention shown in FIGS. 12 and 13, the male elements 111 and female 121 '' '' are complementary recesses formed respectively by the outer edge 113 '"' of the support disc 110 '" "and by the inner longitudinal edge 120 "'" A of each circular segment 120 "", adapted to bear against each other.

Here, the peripheral outer edge of the support disc 110 '"" is formed of a series of circular arcs 113 "'" A ₁ 113 "'" B decentered with respect to the center of the support disc 110'"", these arcs circle connected to each other by said recesses 111 '"".

Again, said recesses 111 "'", 12I' "" in abutment against each other advantageously make it possible to take up the shearing forces, orthoradial, suffered by the cutting tool 100 '"" during the cutting, which preserves the connection by brazing, welding or bonding occurring between the support disc and said segments.

Thanks to this form-fitting arrangement between the male elements (tenons or recesses) and females (complementary notches or recesses) of the support disc and the circular segments, it is possible to use circular segments whose thickness is thinner than that of the segments circular blades segment of the state of the art and have not undergone annealing step (which alleviates the manufacturing process).

Of course according to an alternative embodiment of the invention not shown, it can be provided that the tenons (more generally the male elements) are provided projecting on the inner longitudinal edge of the segments then that the notches (more generally the female elements) are distributed around the periphery of the outer peripheral edge of the support disk. This does not change the technical effect produced by the cooperation of the male and female elements namely the recovery of the orthoradial shear forces experienced by the cutting tool during cutting, but this amounts to just reversing the punctual cooperation means of form between the segments and the support disk.

Preferably, according to the embodiments of FIGS. 1 to 11, said pins 111; 111 '; 111' "111" "come from formation with the support disc 110; 110 '; 110 "; 110"; 111 "" to form a single piece. Here, the support disk 110; 1 10 '; 110 "; 110'", 110 "" and its tenons

111; 111 '; 111 "; 111" "are cut from a steel plate. Such cutting can be achieved using a laser beam.

According to the embodiment shown in Figures 1 and 2, each circular segment 120 has a half-notch 121A at each of its two ends. More particularly, each circular segment 120 has a half-notch 121A provided at the junction of its inner longitudinal edge 120A (intended to be applied against the edge of the support disk) and each of its lateral end edges 122 (see FIG. 2). Each notch 121 receiving a tenon 111 is then formed by the union or association of two half-notches 121A circular segments 120 juxtaposed (see Figure 1).

According to the embodiments shown in Figures 3 to 11, each circular segment 120 ', 120 ", 120" "120" "has a notch 121" 121 "121" "121" "placed in a middle portion its inner longitudinal edge 120'A; 120 "A; 120 '" A; 120 "" A secured to said support disc 110'; 110 "; 110" "110" ";

The length of the smooth inner longitudinal edge 120A, 120A, 120A, 120A, 120A, 120A, of each circular segment 120, 120 ', 120'',120'', 120 ""; 120 "" is much greater than the width of each notch 121 '; 121 "121""121""or half-notch 121 or each recess 121""and each pin 111; 111"; 111 "" 111 "" or each complementary step 111 """, so that the connection between the segments and the support disk is essentially carried out by soldering or welding or bonding, and the mechanical cooperation between the notches and tenons or between the complementary recesses intervenes only in the background, punctually, to reinforce this connection so that it resists the orthoradial shear forces experienced by the cutting tool.

According to the embodiment shown in Figures 3 to 5, 8, 9, 10 and 11 the pins 111 ', 111' "111" "and the notches 121 '; 121" "121" "associated have a shape substantially rectangular. This substantially rectangular shape of the tenons and notches is particularly advantageous because it is simple which allows to easily mount the circular segments on the support disk by bringing each of the segments facing the edge of the support disk in a radial assembly direction ( that is to say by moving each of the segments in the direction of a radius of the support disk).

Such a mounting of the circular segments in the radial direction of the support disc is further facilitated by the complementary shapes of the pins 111 '"111" "and notches 121" "121" "of the cutting tool 100" "100 "" shown in Figures 8 and 9 and 10 and 11. Indeed, here, the back of the pins 111 '"1 11" "and the bottom of the notches 121'" 121 "" associated follow an orientation not parallel but slightly inclined relative to the edge of the support disc 110 '"; 110'".

According to the embodiments shown in Figures 1, 2, 6 and 7, the lugs 111; 111 "and the notches 121; 121" associated have a shape dovetail. The more complex dovetail shape requires mounting the circular segments on the support disk by one of the front or rear faces of the disk by moving each circular segment in an axial assembly direction (i.e., a direction parallel to the axis of rotation of the support disk). Preferably, as shown more particularly in the figures

3, 4, 6, 8, 9, 10, 11, 12 and 13, the end side edges 122 'of the circular segments 120', 120 ", 120", 120 ""; 120 '"" juxtaposed circular cutting tool 100'; 100 "; 100" "100" "100" "are spaced apart from each other so as to form a slot 130 ', 114 130 ", 114", 130 ", 114", 130 "", 114 "" 130 "", 114 "" which is extended in the carrier disc 110 '; 110 "; 110"; 110 "" 110 "" (see FIGS. 4, 6, 9, 11 and 13).

Slots 130 ', 114', 130 ", 114", 130 ", 114", 130 "", 114 "", 130 "", 114 "" allow the expansion gaps of the heterogeneous materials to be accommodated. constituting said circular cutting tool (circular steel tool segments fast and basic steel support disc). They also make it possible to form a barrier to the propagation of heat from one circular segment to the other during the brazing or hot-welding step (the temperature is around 800 ^° C.) which is carried out over the entire length. the inner longitudinal edge of each circular segment. This is particularly advantageous because it is thus avoided that the soldering or hot welding of each circular segment on the support disk does not cause the soaking and thus the embrittlement of the following circular segment in position on the support disk.

As shown more particularly in Figures 4, 6, 9, 11 and 13 preferably, the bottom 115 '115 "115" "115" "115" "of each slot 1 14'; 1 14 "; 1 14" '; 1 14 ""; 114 '"" provided in the carrier disk 1-10'; 110 "; 110"; 110 ""; 110 '"" forms a circular opening.

Thus, advantageously, each circular opening of the support disk 110 '; 110 "; 110" "110" "; 110" "locates the deformation in a sound zone of the support disk 110'; 110"; 110 '"; "110" ", i.e. in an area that is not thermally affected by brazing or welding the circular segments on the disk.

Preferably, the ends 130 ', 114', 130 ", 114", 130 ", 114", 130 "", 114 "", 130 "", 114 "" form liquid reserves. coolers that bring this liquid into the cup.

The arcuate construction 113 "'" A, 113' "" B of the periphery of the carrier disk 110 "" of the embodiment of the invention shown in FIGS. 12 and 13, is constructed so that each arc of circle of each pair of circular arcs 1 13 "" Α, 113 '"" B provided between two successive slits 130 "" 114 "" has an end tangentially connected to a circle C1 centered on the center of the disc support 110 '"" and whose radius extends to the top of the recess i 11' "" corresponding said support disk. In other words, the arc 113 "'" Starting from a slot 130' "", 114 '"" is connected to the circle C1 by its end adjacent the recess 111' "", while the next circular arc 1 13 "'" B starting from the recess 111' "" is connected to the circle C1 by its end adjacent the other slot 130 '"", 114 (see Figure 13).

The smooth inner longitudinal edge 120 "'A of each circular segment 120'""attached to the disk 110 '""follows a line in two arcs. complementary to those of the support disc 110 '"", which are interconnected by the recess 121'"" provided in the middle part.

As shown more particularly in FIG. 4, the edges 122'A of said end lateral edges 122 'of the circular segments 120' are chamfered.

These chamfers 122'A make it possible to facilitate the putting back on line of each circular segment inside the cut made in case of slight deviation of said circular segment with respect to the juxtaposed circular segment already engaged in the cut. According to the examples shown in FIGS. 3, 4 and 6, said slots

130 ', 114'; 130 ", 114" separating the juxtaposed circular segments extend along spokes of the support disk.

According to the embodiments shown in FIGS. 8, 9 and 12, 13, said slots 130 '', 114 '", 130' '", 114' '"separating the circular segments 120'"; 120 '"" juxtaposed extend in an inclined direction I with respect to the radial direction R of the support disc 110 '"; 110'" ". Preferably, the angle of inclination A1 of the slots 130 "', 114" "with respect to the radii R of the support disk 110" is of the order of 15 °.

The inclination I of the slots relative to the spokes of the support disk advantageously makes it possible to ensure the engagement of the circular segments in the cut made. Indeed, thanks to this inclination, the zones 120 "C and 120" D of two circular segments 120 '"which follow each other, situated on either side of the slot 130'" inclined, are always engaged simultaneously in the cut made. The engagement of said zone 120 "'D of the following circular segment 120'", simultaneously with the engagement of the preceding circular segment 120 '", forces it to enter the cut even if it is slightly deviated with respect to the segment In addition, advantageously, as will be explained in more detail with reference to the embodiment of FIGS. 10 and 11, the inclination of the slots 130 '";130""" is such that it follows the line grinding the teeth of the teeth 120 "'B;120'""B of the tool. Thus, throughout the lifetime of the tool, despite the successive sharpening of the teeth of its teeth 120 "'B;120'""B, the position of each slot 130""; 130 '""separating two circular segment 120 '";120'""adjacent, remains constant with respect to the cutting edge of said segments. According to the embodiment of the cutting tool shown in the figures

10 and 11, each slot 130 "", 1 14 "" separating two adjacent circular segments 120 "" extends along a line forming a recess with two end portions 130 "" A, 130 "" C and a central portion 130 "" B transverse establishing the junction between the two end portions 130 "" A, 130 "" C.

Here, said central portion 130 "" B of each slot 130 "" connects to both end portions 130 "" A, 130 "" C by inverted bends. In addition, said central portion 130 "" B of each slot 130 "" extends over a portion of circle C concentric with the peripheral edge of the support disc 110 "". As in the embodiment of Figures 8 and 12, at least the end portion 130 "" A of each slot 130 "" opening on the teeth 120 "" B of the tool, extends in a direction I inclined relative to the radial direction R of the support disc 110 "". Here the two end portions 130 "" A, 130 "" C of each slot 130 "" are parallel and inclined with respect to the radial direction R of the carrier disk 110 "". The angle of inclination A1 is of the order of 15 °.

The inclination I of the end portion 130 "A emerging from the slots 130" "relative to the spokes R of the support disk advantageously allows the engagement of the circular segments in the cut made. Indeed, thanks to this inclination, the zones 120 "" C and 120 "" D of two circular segments 120 "" which follow each other, located on either side of this end portion 130 "" A inclined of the 130 "slot, are always engaged simultaneously in the cut made. The engagement of said zone 120 "" D of the following circular segment 120 "", simultaneously with the engagement of the preceding circular segment 120 "", forces it to enter the cut even if it is slightly deviated with respect to the segment previous. In addition, advantageously, the inclination I of the end portions 130 "" A slots 130 "" is made such that it follows the sharpening line F teeth of the teeth 120 "" B of the tool. Thus, throughout the life of the tool, despite the successive sharpening of the teeth of its teeth 120 "" B, the position of each slot 130 "" separating two circular segments 120 "" adjacent, remains constant relative at the cutting edge of said segments.

Advantageously, according to this embodiment, the circular segments 120 "" are pairwise linked together. The connection S2 between two circular segments 120 "" is produced by soldering, welding or gluing. concentrically to a portion of said slot 130 "" separating said segments. More particularly, said portion of each slot 130 "" surrounded by said link S2 is said central portion 130 "" B of the slot 130 "" extending along a portion of circle C. This inter-segment connection makes it possible to avoid circular segments 120 "" to misalign and disrupt the cutting performance of the tool.

Advantageously, the method of manufacturing the circular cutting tool 100; 100 ", 100", 100 "", 100 "" is to cut circular segments 120, 120 ', 120 ", 120", 120 "" 120 into heat-treated steel plates; "" "comprising on a smooth longitudinal inner edge at least one notch 121 '; 121"; 121' "; 121" "or a half-notch 121A or a succession of two circular arcs connected by a recess 121 '" ", cut into a steel plate a support disc 110; 110 '; 110 "; 110" 110 "" 110 "" with protruding on its periphery pins 111; 111 "; 11"; 111' "111" "or a succession of off-center circular arcs 113" "A, 113 '" "B which are connected two by two by recesses 111'" ", to relate said circular segments 120; 120 '; 120 120 "" 120 "" 120 "" on the periphery of the support disc 110; 110 "; 110"; 110 "; 110" "110" "so that said tenons 111; 111 '" "; 111 ", 111" "111" "of the disk engage in said slots 121; 12f; 121"; 121 "; 121" "segments or that the recesses complement 111 '"", 121' "" abut against the others, and to join by brazing, welding or gluing said circular segments to the support disk along the smooth sections (along the line S1), avoiding joining by soldering welding or gluing the male and female elements cooperating mechanically with each other.

Advantageously, according to this method, circular segments 120, 120 ', 120 ", 120'", 120 "", 120 "" whose thickness is greater than the thickness of the support disc 110, 110 ', 110 are used. "110" "110" "so that said circular segments 120; 120"; 120 "; 120"; 120 ""; 120 "" reported on the support disk 110; 110 '; 110 "110" "110" "110" "protrude from the two opposite front and rear faces of the base disk (see Figure 4).

The cutting of the circular segments and the support disk can be performed by means of a laser beam. To report on the above-mentioned segments 120 '; 120 ";120"; 120 ""; 120 "" on the support disk 110 '; 110 ";110"; 110 ""; 110 "", the edges 122 ¹ A are chamfered at the end lateral edges 122' of said segments. The brazing of the circular segments on the support disk is carried out at about 800 ° C. The welding is advantageously a laser welding.

According to the method, it is also possible to join the circular segments 120 "" to each other. This connection is also achieved by soldering, welding or gluing concentrically to a portion of the slot separating two adjacent segments. In the case shown in FIGS. 10 and 11, the intersegment connection is made around the central portion 130 "" B of each slot 130 "" which extends along a concentric portion of circle C to the circular peripheral edge of the support disc 110 "".

According to the method, after brazing, welding or gluing said circular segments 120, 120 ', 120 ", 120", 120 ""; 120 '"" on the support disk 1 10; 110'; 110 "; 110"; 110 "; the cutting teeth 120B, 120B, 120B, 120B, 120B, 120B, segments are corrected; forming thereon lateral struts oriented on the side of the opposite front and rear faces of the support disk and possibly radial struts oriented substantially perpendicularly to the opposite front and rear faces of the support disk.

The characteristic that the cutting teeth 120B, 120B, 120B, 120B, 120B, 120B segments are cut on all their faces makes it possible to increase the cutting performances of the cutters. the circular cutting tool 100; 100 '; 100 ";100""100""The performance gain can be estimated at 20% and comes mainly from the fact that the friction of the teeth thus cut on the material to cut is reduced and thus the cutting edges of these teeth are heated less. Indeed, warming is a major factor of collapse of the cutting edges of the active cutting part made of quick tool steel. In addition, advantageously, after their grinding, a surface treatment is performed on the cutting teeth of the circular segments. In particular, the surface treatment may consist in applying a vacuum vapor deposition coating which improves the properties of sliding of the tool, its superficial hardness and which makes thermal barrier also increasing the resistance of the cutting edges.

The number and the characteristics of the thermal treatments of the circular segments and the support disk depend on the steels used. They can be made in oven, vacuum, carpet, flame, induction or with a laser. Generally, we first make a quench then between one and three incomes.

According to the method, there is also provided a finishing step (marking and packaging) of the circular cutting tool 100; 100 '; 100 "; 100" "100" "; 100" "' which depends on the product range and the needs of the user.

The main advantage of the circular cutting tool 100; 100 '; 100 ", 100", 100 "" 100 "" is a relatively low cost price. In addition, its design offers wide possibilities in the realization of the circular cutting tool such as the realization of the cooling fluid circulation slots or as the straightening of the teeth of the teeth etc. Finally, because of the use of the fast tool steel segments, it is possible to obtain coated cutting edges (by surface treatment of only the segments) for large diameters of cutting tools (diameter equal to 2200 mm) which gives The tool cuts great performance to cut some complex products such as sections with large sections.

Claims

1. Circular cutting tool (100; 100 '; 100 "; 100"'; 100 ""; 100 '"") which comprises a carrier disk (110; 110'; 110 "; 110 '"; 110 ""; 110 "" ") and a plurality of circular segments (120; 120 '; 120"; 120 ""; 120 ""; 120 "'") provided with cutting teeth, attached to the periphery of the carrier disk, characterized in the support disc (110; 110 "; 110"; 110 "" 110 ""; 110 "'' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' '' ''; the smooth, groove-free or rib-free inner longitudinal edge of each circular segment (120; 120 '; 120 "; 120"; 120 ""; 120 ""), and in that it is provided locally on said smooth outer wafer of the carrier disk and on said circular segments, male elements (111; 11 '; 11' '; 11' '; 11' '; 11' '' ') and females (121; 121 '; 121'; 121 ''; 121 ''; 121 '' ") cooperating mechanically with each other without being joined to each other brazing, welding or gluing, to take orthoradial shear forces experienced by the cutting tool.

2. Cutting tool according to claim 1, characterized in that said male and female elements are interlocking means nested in each other.

3. Cutting tool according to claim 2, characterized in that the male elements are tenons (111 '; 111' "; 111" ") and the female elements

(121 '; 121' "; 121" ") are notches having a substantially rectangular shape.

4. Cutting tool according to claim 3, characterized in that the back of the tenons (111 "'111" ") and the bottom of the notches (121'"; 121 "") associated follow an inclined orientation relative to the edge of the support disk (110 '"; 110" ").

5. Cutting tool according to claim 2, characterized in that the male elements are pins (111; 111 ") and the female elements (121; 121") are notches having a substantially dovetail shape.

6. Cutting tool according to claim 1, characterized in that the male and female elements (11 '"", 121 "") are complementary recesses respectively formed by the outer edge (113 "") of the support disk (110'). "") and the inner longitudinal edge (120 '"" A) of each circular segment (120'""), adapted to bear against each other.

7. cutting tool according to the preceding claim, characterized in that the peripheral outer edge of the support disc (1 10 '"") is formed of a succession of circular arcs (113 "'" A, 113 '"" B ) off-center with respect to the center of the support disc, these arcs of circle being connected to each other by said recesses (111 '"").

Cutting tool according to one of the preceding claims, characterized in that each circular segment (120 ', 120 ", 120'", 120 "", 120 "") comprises one of said male or female elements placed in a part median of its slice secured to said support disk (110 '; 110 "; 110" "110" "; 110" ").

9. cutting tool according to one of claims 1 to 5, characterized in that each circular segment comprises a male or female elements placed at each of its two ends.

10. Cutting tool according to the preceding claim, characterized in that each circular segment (120) has a half-notch (121A) at each of its two ends, the meeting of two half-notches (121A) of circular segments (120). juxtaposed forming a notch (121) receiving a pin (111) provided projecting from the outer edge (113) of the support disc (110).

11. Cutting tool according to one of claims 1 to 5 and 9, characterized in that the support disc (110; 110 '; 110 "; 110" "; 110" ") projecting from its outer edge (113; 113 '; 113 ") a plurality of tenons distributed around its periphery, engaged in notches (121; 121'; 121"; 121 '"; 121" ") provided in correspondence on an edge of said circular segments.

12. Cutting tool according to the preceding claim, characterized in that said pins (111; 111 '; 111 "; 111'"; 111 "") come de formation with the support disc (110; 110 '; 110 "; "110" ") to form a single piece.

13. Cutting tool according to one of the preceding claims, characterized in that the end side edges (122 ') of the juxtaposed circular segments (120') are placed at a distance from each other so as to form a slot (130 ') which is extended in the support disk (110').

14. Cutting tool according to the preceding claim, characterized in that the bottom (1 15 '; 1 15 "; 1 15'"; 1 15 "" 1 15 '"") of each slot (114'; 114 "; 1 14 '";114""114'"") provided in the carrier disk (110 ';110"; 110 ""; 110 ""; 110 "") forms a circular opening.

15. Cutting tool according to one of claims 13 and 14, characterized in that the edges (122'A) of said end side edges (122 ') of the circular segments (120') are chamfered.

16. Cutting tool according to one of claims 13 to 15, characterized in that said slots (130 ', 114'; 130 ", 114") separating the circular segments

(12O ¹ ; 120 ") juxtaposed extend along spokes of the support disk.

17. Cutting tool according to one of claims 13 to 15, characterized in that said slots (130 '", 114'", 130 "", 114 "") separating the circular segments (120 '"; 120" ") juxtaposed extend in a direction inclined relative to the radial direction (R) of the support disc (110 '", 110" ").

18. Cutting tool according to the preceding claim, characterized in that the inclination of said slots (130 '", 114'") is of the order of 15 ° relative to the spokes (R) of the support disc (110 '") .

19. Cutting tool according to one of claims 13 to 15, characterized in that each slot (130 "", 114 "") separating two adjacent circular segments (120 "") extends along a line forming a recess with two end portions (130 " ¹¹ A ₁ 130""C) and a central portion (130""B) transverse establishing the junction between the two end portions (130""A,130""C).

20. Cutting tool according to the preceding claim, characterized in that said central portion (130 "" B) of each slot (130 "") is connected to the two end portions (130 "" A, 130 "" C) by elbows with inverted curvatures.

Cutting tool according to one of the two preceding claims, characterized in that said central portion (130 "" B) of each slot (130 "") extends over a portion of a circle concentric with the peripheral edge of the support disc ( 110 "").

22. Cutting tool according to one of the three preceding claims, characterized in that at least one of the end portions (130 "" A, 130 "" C) of each slot which opens on the toothing (120 "" B ) of the tool, extends in an inclined direction (I) relative to the radial direction (R) of the support disc (1 10 "").

Cutting tool according to the preceding claim, characterized in that the two end portions (130 "" A, 130 "" C) of each slot (130 "") are parallel and inclined relative to the spokes of the support disk ( 110 "").

24. Cutting tool according to one of the two preceding claims, characterized in that the inclination of each end portion (130 "" A, 130 "" C) of each slot (130 '") is of the order 15 ° with respect to the spokes (R) of the support disc (110 "").

25. Cutting tool according to one of the preceding claims, characterized in that the circular segments (120 "") are two by two linked together.

26. Cutting tool according to the preceding claim and one of claims 13 to 25, characterized in that the connection (S2) between two circular segments (120 "") is achieved by brazing, welding or gluing concentrically to a portion of said slot (130 "") separating said segments.

27. Cutting tool according to claims 26 and 21, characterized in that said portion of each slot (130 "") surrounded by said connection is said central portion (130 "" B) of the slot extending along a portion of a circle .

Cutting tool according to one of the preceding claims, characterized in that the carrier disk (110; 110 '; 110 "; 110'"; 110 ""; 110 "") is made of a base steel selected from alloy and non-alloy steels, cold-working tool steels and hot-work tool steels and circular segments (120; 120 '; 120 "; 120' '; 120"'; 120 '""); are made of high-speed tool steel which, compared to alloy or non-alloyed steels, cold tool steels and hot-tool steels, has a higher hardness and resistance after quenching at high temperatures. at about 600 ° C.

Cutting tool according to the preceding claim, characterized in that the circular segments (120, 120 ', 120 ", 120'", 120 "", 120 "") are made of a fast tool steel selected from steels ABC3, M2, M35, M42, ASP2060 and M51.

30. A method of manufacturing a circular cutting tool according to one of the preceding claims, characterized in that cutting into heat-treated steel slabs recesses (120; 120 '; 120 "). 120 ""; 120 "" 120 "") comprising on a smooth longitudinal inner edge at least one male or female element, a support disk (110; 110 '; 110 "; 110) is cut from a steel plate; 110 ""; 110 """) with male or female elements on its periphery, the periphery of the support disk (110; 110 ';110"; 110 "" 110 ""; 110 "") is reported; ") said circular segments (120, 120 ', 120 ", 120", 120 "", 120 "'') so that said male and female elements mechanically cooperate with each other, and the longitudinal edge is soldered, soldered or glued together. smooth interior of said circular segments (120; 120 '; 120 ";120"'; 120 ""; 120 '"") to the smooth outer edge of the carrier disk (110; 110'; 110 "; 110 '";"; 110 '"") avoiding to secure said male and female elements cooperating with each other.