FR2533475A1 - STRAWBERRY ALESER - Google Patents

Abstract

THE INVENTION CONCERNS ANNULAR BURRING CUTTERS. IT RELATES TO AN ANNULAR BORING CUTTER WITH ALTERNATE TEETH 18 HAVING THREE CUTTING EDGES 34, 36, 38 AND THE END OF WHICH INCLUDES TWO OFFSET SIDES 56, 58, CUTTING AT THE LEVEL OF A RIDGE 60. THE INTERMEDIATE TEETH ARE THE SAME, BUT RIDGE 60 IS NOT LOCATED IN THE SAME LOCATION. IN THIS WAY, SHAPED CHIPS ARE NARROW AND CAN EASILY ESCAPE THROUGH FLUWS 22. APPLICATION TO MILLING TOOLS.

Description

The present invention relates to strawberries

nails to be bored.

  Experience has shown that the duration and effectiveness

  of a boring mill, that is, the ease of feed in a metal workpiece and the finish obtained with a reaming mill, depend to a large extent on the ease with which the chips are cut and with which the cut chips can

  escape from the cutting edges and enter the gou-

  formed around the outer periphery of the cutter and back up When the chips formed by a reaming ring mill can not move freely from the cutting edges and / or when the flutes are clogged or

  clogged with chips, the torque and thrust required

  In advance of the milling cutter, the milling cutter has a rapid wear and the finish of the formed hole is degraded. Attempts to increase the yield of ring burrs have already met with some success. No. 3,609,056 represents an annular bur in which each tooth is intended to cut a single chip. The successive teeth are divided into groups of three and each tooth of each group has a configuration enabling it to cut a chip. of which the width is about one third of the width of the tooth. US Reissue Patent No. 28,416 discloses an annular burr to be bored in which each tooth has multiple edges.

  radially arranged and circumferentially offset

  The lower face of each tooth has flanking faces inclined radially in opposite directions and forming a space, these faces intersecting a ridge directed towards the

  low which itself cuts the outer cutting edge radia-

  Every cutting edge is made so that it cuts out an individual chip.

  shavings, the configuration of the cutter is such that

  The widest skin that is cut has a width that does not exceed the depth of the flutes at the outer periphery of the cutter In this particular cutter, the continuous portion of the sidewall of the cutter has a single inner cutting edge More strawberries Recent developments have been made in a manner different from that described in US Reissue Patent No. 28,416 because in these more recent milling cutters the continuous portion of the milling cutter is formed with two offset cutting edges. circumferentially and not a single cutting edge Although these recent milling cutters allow the use of a greater thickness-of material and a less deep flute, they do not always give perfectly satisfactory nevertheless, especially when they

  are used in large production applications.

  It has been determined according to the invention that the difficulties

  difficulties encountered in the attempts to obtain a free circulation and without hindering the chips to the outside,

  the flutes of an annular bur, were due

  the fact that, as soon as a chip is cut, it expands in all directions Thus, just after cutting, a chip has a width greater than that of the cutting edge by which it was formed In the case of

  burs with circumferentially offset cutting edges

  on each tooth, when the width of the chips cut by the internal cutting edges of each tooth is

  less than the depth of the flutes formed at the

  When the chips are relatively rigid, they should not have a tendency to clog the flutes, at least theoretically. However, the free circulation of these narrow chips upwards in the flutes is in fact prevented in many cases.

  case by the chips cut by the external cutting edges.

  In milling cutters with irregularly shaped cutting edges

  conferringly, the external cutting edges

  at their inner ends radially, against a

  circumferential shoulder formed on the cutter

  sequence, when the chip cut by such an outer cutting edge expands, it tends to get stuck between this

  shoulder and the wall of the cut hole.

  fishing up the chip away from the cutting edge, this condition requiring a larger torque and

  greater thrust and causing less wear and tear

  puncture of the tool and a bad finish of the surface -

  Under certain cutting conditions of a certain material, flutes often become clogged and

blades break.

  The problem of chip entrapment cut by the outer cutting edge obviously arises in cutters of the type shown in the aforementioned US Reissue Patent No. 28,416. In addition, when the inner cutting edge is disposed in any the thickness of the

  wall between the successive teeth, the circulation of

  relatively broad skin cut by this inner edge, radially

  outwardly in the adjacent flute, is

often embarrassed.

  The invention essentially relates to the

  a cutter which ensures an effective cut and which is intended to promote a free flow of chips in the flutes of the cutter, without obstacle, from

all the cutting edges of the teeth.

  The invention also relates to a cutter of the type described above in which the external cutting edges are made so that they cut a chip having a width much smaller than that of the edges.

  cutting and avoid the jamming described above.

  is lying. The invention also relates to an annular cutter having staggered cutting edges made in such a way that the inner and outer cutting edges cut chips that are smaller in width than the edges.

corresponding cutting.

  More specifically, the invention relates to the reso-

  the problem of jamming the chips formed by

  the outer cutting edges of a ring-type milling cutter

  jures having offset internal and external cutting edges, by vertical clearance of the outer faces of one tooth out of two and by vertical clearance of the internal faces of the intermediate teeth so that the radially outer portion of the outer cutting edge of a

  first tooth cuts a thick chip whose width is

  lower than the outer cutting edge, and that the radially inner portion of the outer cutting edge of the next tooth also cuts a thick chip having

  approximately the same width, the two chips being

  narrower than the flute is deep.

  In the preferred embodiment, the width of the inner cutting edge corresponds to the wall thickness and the radially inner portion of the uncut inner faces without clearance is stripped in a manner-ulus

  important that the detalted faces stripped.

  Other features and advantages of the invention

  tion will become more apparent from the following description,

  with reference to the accompanying drawings in which: Figure 1 is a perspective of a milling cutter according to the invention; Figure 2 is a partial perspective of the cutter; Figure 3 is a partial elevation of the cutter, seen from the front face of one of the teeth; Figure 4 is a bottom view of the tooth shown in Figure 3; Figure 5 is a partial elevation of the tooth as shown in Figure 3; Figure 6 is a bottom view of the tooth shown in Figure 5; Figures 7 to 7 j represent the progression of the successive teeth of the cutter in a room; Figure 8 is a perspective of a strawberry variant according to the invention; Figures 9, 10, 11, 12 and 13 are views corresponding to Figures 2 to 6 but in the case of the strawberry variant of Figure 8;

  Figures 14a and 14b are schematic elevations

  representing the progression of two successive teeth

  Sives of the strawberry of Figures 8 to 13, in a room; and

  Figures 15 and 16 are elevations

  two successive teeth of another strawberry variant. The annular boring cutter according to the invention is intended to form holes in metal and has the general reference 10 in FIG.

  body 12 and a stem 14 The body 12 has a shape of

  shovel, having a side wall 16 whose length

  is greater than the thickness of the room in the

  The lower end of the side wall 16 has, at its periphery, a plurality of circumferentially spaced apart cutting teeth. In the embodiment shown, the cutting teeth are distributed.

  into two groups, those of the first group carrying the reference

  The teeth 18, 20 are arranged alternately so that a first tooth 20 is circumferentially disposed between successive teeth 18. A spiral flute 22 rises around the outer periphery of the milling cutter. of each tooth The successive flutes 22 are separated by a bearing surface 24 formed at the outer periphery of the cutter.

  front edge of each span 24 has a narrow margin 25.

  The portions of the annular side wall 16 of the cutter between the successive teeth 18, 20 form cheeks 26 The radially outer face 28 of each cheek 26

  delimits the radially inner wall of each flute 22.

  The depth of the flute 22 is approximately equal to

  the thickness of the cheek 26 or it may be slightly higher than

  less than this thickness Each flute has a circumferentially anterior lateral wall 30 and

  a circumferentially posterior lateral wall 32.

  In the cutter shown in the figures, each

  that tooth 18, 20 has three cutting edges 34, 36, 38 The edge 38 has two portions 38a, 38b as previously described The cutting edge 34 is placed a distance forward in the direction of rotation, from the edge of cutting 36, and the latter is shifted forward in the direction of rotation relative to

  at the cutting edge 38 The cutting edge 34 is at the

  lower end of the posterior face 40 of an internal groove 42 formed in the cheek 24 The upper end of the groove 42 is inclined radially outwards and rises as indicated by the reference 44 The cutting edge 36 is placed at lower end of the posterior face 46 of a secondary groove 48 which is also

  mee in the cheek 26 directly near the internal throat 42.

  The upper end of the secondary groove 48 is

  upward radially outwardly as

  50, above the internal groove 42.

  The cutting edges 34, 36 are separated by a shoulder

  circumferential 51, at the lower end of the radial face

  The cutting edge 38 is at the lower end of the posterior face 32 of the flute 22 and is offset back from the edge of the groove 48.

  cut 36, by a shoulder 54 formed at the lower end

flute 22.

  The lower face of each tooth has two faces 56, 58 which are delaminated and define a certain space. In the operating condition of the cutter (FIG.

  radially inner relined face 56 is axially inclined

  upwardly and radially inwardly while the radially outer relief face 58 tilts

  axially upwards and radially outwards.

  In addition, each of these relief faces is inclined upwardly from the respective circumferential cutting edges by a relatively small amount, such as 8 to 10 degrees, so that the space required relative to the cutting edges is delimited when the tool rotates The two trimmed faces 56, 58 intersect at a downwardly directed ridge 60 which itself cuts the radially outer cutting edge 38 and thus divides it into a radially outer edge portion 38a and a radially internal edge portion 38 b The radial inclination of

  the relief face 58 is between about 5 and 35 degrees

  compared to the horizontal and is preferably

  approximately 10 degrees. The internal scallop face 56 is

  radially bent with respect to the horizontal with an angle of between 3 and + 25 degrees and preferably of approximately degrees Given the inclination of the relief faces

  56, 58 in the radial direction and in the circumferential direction

  Similarly, the cutting edges 34, 36, 38 are not only circumferentially offset as shown in FIGS. 4 and 6 but are also vertically offset, seen from the front face of the tooth as shown in FIGS.

Figures 3 and 5.

  When using the strawberry described above,

  previously, the chips cut by the cutting edges 34, 36 have a width less than the depth of the flutes

  22 and can easily fit into these flutes.

  However, when the cutting edge 38 cuts a chip over its entire width, as soon as this chip is cut, it expands and tends to get caught between the shoulder 54 and

  the wall of the hole being cut. The invention is

  to avoid this jamming effect by cutting, by

  each outer cutting edge 38, of a chip whose

  is smaller than the edge 38.

  It should be noted that the ridge 60 formed on the tooth 18 is disposed radially inwards relative to

  at the crest 60 formed on the tooth 20 The crests 60 decays

  radially on the successive teeth of the strawberry

  are due to the fact that, on each tooth 18, the detachment face

  born 58 is vertically undercut throughout its range.

  due radial upwards from the detroned face

  58 of each tooth 20 This phenomenon would provoke the

  radially inwardly of the ridge of each tooth 18 relative to the ridge 60 of each tooth 20 According to the invention, the detented face 56 of each tooth 20 is flush in a similar manner throughout its entire extent radially upwards with respect to the cut face 56 of each tooth 18 The clearance of the trimmed faces 56 of the teeth 20 causes the ridges 60 to move radially outwards with respect to the

  ridges 60 of the teeth 18, of an additional quantity.

  The importance of the vertical clearance of these relief faces is not essential, but in any case, it must be greater than the theoretical load desired chip on each tooth For example, when advancing a cutter to six teeth of 0.3 mm per turn, the

  theoretical chip load on each tooth is 0.05 mm.

  Thus, if the theoretical chip load on each tooth is 0.05 mm, the trimmed faces 56, 58 must have a vertical draft as previously described on a

  distance greater than 0.05 mm In practice, if we

  that a chip load of 0.05 mm is a

  normal chip number for which a tool can function

  and a chip load of approximately 0.125 mm is

  a normal maximum load with which a milling cutter

  of this type is used, the vertical clearance, on the trimmed faces 56, 58, must be between 0.075 and 0.3 mm. However, in the case of large thick strawberries, the advance may be such that the chip load

  significantly exceeds 0.125 mm; the remains must then

  In practice, it is preferable that

  surface area is between 0.175 and 0.25 mm and is preferably of the order of 0.225 mm It should be noted that the maximum extent of the draft depends on the angles

  of radial inclination of the relieved faces and the

  of the outer cutting edge so that, after clearance, the ridge 60 again intersects the outer cutting edge 38 and

  not the intermediate cutting edge 36.

  It is highly desirable that the inner and outer cut-away faces are stripped so that the

  successive tooth ridges have a radial

  equal to the central radial line of the flute When the ridges are so arranged, the outer cutting edges of the successive teeth cut chips of roughly constant width, each being only slightly greater than half the depth * In this way, all chips leave

  a maximum space in the flutes 22.

  The cutting action provided by the tool such as

  previously described is better represented by the progress

  FIGS. 7A to 7B These figures show an annular mill of the type described having six teeth.

  teeth 1, 3 and 5 (as shown to the left of the figure).

  1) correspond to the teeth 18 on which the relief face 58 has a vertical clearance and the teeth 2, 4 and 6 of FIG. 7 correspond to the teeth 20 whose radially internal relief face 56 has a vertical clearance. Successive views 7 to 7, from top to bottom, indicate

  the action of the successive teeth of the strawberry for

  successive rotational movements equal to the pitch of successive teeth

  sive. In Figure 7a, the cutter is shown in

  the position in which the cutting edge 36 has just

  started to penetrate into the upper face of the room and

  thus cutting a narrow chip 62 from the upper face

  In this position, the cutting edge 38 in the upward direction of tooth # 1 has not yet been in contact with the workpiece and the lowest point of the edge

  cutter 34 is ready to come into contact with the part

  that the cutter rotated one step of the teeth and advanced axially from the position of Figure 7a, the edge

  38 of the tooth N O 2 penetrates into the workpiece

  The cutting edges 34, 36 of the tooth n O 2 have a vertical clearance over a distance greater than the theoretical chip load formed by the advance

  axial axis and thus the cutting edge 36 is actually

  above the groove previously formed by the corresponding edge.

laying 36 of tooth N O 1.

  After the next elementary rotation and the

  this next axial of the cutter (Figure 7 c), the chip 62

  formed by the cutting edge 36 of the tooth 3 is relatively

  The cutting edge 34 of the NO 3 tooth cuts the chip 66. The radially inner portion of the cutting edge 38 formed on the tooth 3 begins to cut and form. a

  When the tool rotates by another amount

  7d), the radially outer portion of the cutting edge 38 cuts a throat wider and deeper than that cut previously by the edge 38 of the tooth n O 2 so that the chip 64 is wider and thicker that the chip formed by the inner portion of the cutting edge 38 of the previous tooth As the edges 34, 36 of the tooth NO 4 have a vertical draft over a distance

  greater than the chip load, they are placed

  above the bottoms of the groove formed by the cutting edges

  corresponding to tooth No. 3 Figure 7 e shows the ac-

  cutting ratio of tooth N O 5 after an elemen-

  The cutting edges 34, 36 then cut a chip 62, 66 over the entire width, but only the radially inner portion of the cutting edge 38 is effective so that the chip 68 thus cut has a width greater than that chip cut by the party

  internal cutting edge 38 of tooth N O 3.

  Although the chips 62, 66 have a width

  corresponding to that of the cutting edges 36, 34

  Although these chips expand to a certain extent immediately after their formation, they do not tend to get stuck in the strawberry if they are relatively narrow

  since, as soon as the chip 66 is formed, it is directed

  outwardly in the adjacent flute 22 by the upper face 44 of the groove 42. As soon as the chip 66 is formed, it is directed radially towards the flute 42.

  the outside in the adjacent flute 22 by the upper face

  Thus, the narrow chips formed by the cutting edges 34, 36 are directed into the adjacent flute 22 just after their formation.

  and since the radial depth of the flute 22 is clearly

  more than the width of the chips 62, 66, these normally flow freely upwards

in the flute without being embarrassed.

  Figures 7 e to 7 j show that when all the cutting edges have entered the part, each of the

  cutting edges 38a and 38b form a chip of smaller width

  Therefore, the radially outer portion of the edge 38, on each alternating tooth, cuts a chip 64 and the radially inner portion of each cutting edge of the intermediate tooth cuts a chip 68. As a result, as each of the chips 64, 68 has a width less than the depth

  radial flute 22, these chips move freely

in the flutes.

  As the ridged faces 56, 58 have a de-

  vertical canoe alternating as described, higher than the theoretical charge of the chips, it should be noted that, when all the teeth have entered the room, all the chips are relatively thick and have a thickness

  actual maximum that exceeds the theoretical load of

  skin When the chips are relatively thick, they tend to remain in the general rectilinear form instead of wrapping tightly; therefore, they do not tend to nest in other chips and thus they move more easily upwards in the flutes of the cutter In addition, as all the cut faces 58 are inclined relative to the following horizontal a

  relatively small angle, preferably about 10

  the chips cut essentially by the edge portion 38a are generally directed directly along the flute instead of being directed radially towards the flute.

  inside against the radially inner face of the body.

  Swear free circulation of all chips formed by the cutting edges, upwards in the flutes, is

thus facilitated without obstacle.

  As indicated previously, when the flow of chips from the cutting edges and going up in the flutes is not disturbed, the torque and the thrust

  necessary for the penetration of the strawberry are consid-

  Similarly, the cutting edges become dull

  much slower and the duration of the strawberry is extended.

  In addition, as the cutting edges remain sharp and as the chips do not get caught against the wall of the hole formed, the surface finish thus obtained is significantly

  greater than that obtained with known strawberries.

  According to the invention, the cutting edges 34, 36

  alternating teeth only have a cutting action

  the cutting edges 34, 36 of the teeth 20 (i.e., the numbered teeth 2, 4 and 6 in the embodiment of FIGS. 1 to 7 j) do not provide any cut, the edges of

  cut 34, 36 of these teeth can be totally removed.

  The operation can easily be carried out by

  removing each tooth 20 completely by grinding along its width as indicated by the broken radial line 70 in FIGS. 2 and 4 In this case, only the teeth 18 have the inner cutting edges 34, 36 When the teeth have only one edge outer cut 38, the circumferential extent of each tooth is relatively short and, as each tooth 20 cuts only one narrow chip, the adjacent flute 22 may have a width

  much lower circumferential than that of gou-

  adjacent to the teeth 18 which must house these co-

  Thus, when the teeth 20 have only one cutting edge, a larger number of teeth can be formed on a milling cutter with a predetermined diameter.

  more teeth makes it possible to obtain not only

  a more robust milling cutter, but also ensures a faster cut for the same surface speed. Moreover, as only part of the cutting edges of each tooth actually ensures cutting, the remaining parts are

  easily flooded by the cooling fluid

  in the passage formed in the stem of the strawberry,

  so that the heat released can be quickly dissipated.

  The cutter shown in FIGS. 8 to 14 b is generally of the type shown in the above-mentioned United States Reissue Patent No. 28,416.

  differs from that described above

  in that each tooth is formed with only two cutting edges instead of three, the inner edge of

  cut 35 being disposed over the entire thickness of the cheek 26.

  For reasons indicated hereinafter, although the inner cutting edge 35 has a width which corresponds to the thickness of the cheek 26, the latter can

  have a thickness equal to about half of the thickness

  If the inner cutting edge 35 is placed over the entire width of the cutter, it is sufficient that a single groove

  42 is formed between the successive teeth.

  As in the embodiment already described, the offsetting outer faces 58 of the difts 18 on L have a vertical draft and the internal detachable faces 56 of the teeth 20 have a similar undercut. Thus, the peaks of the successive teeth are offset radially from the tooth.

  same way as in the embodiment described above.

  However, in the embodiment of the

  8 to 14b, in which the internal cutting edge 35 is placed over the entire thickness of the cheek 26, the internal detachable faces 56 of the teeth 18 are stripped as

  shown in FIGS. 9, 12 and 13.

  born are stripped up on only one part

  their width, that is to say the most

  The inner cutting edges 35 of the teeth 18 are thus divided into a radially inner portion 35a and a radially outer portion 35b. As shown in FIGS. 9 and 13, the relief faces of the teeth 18 are stripped of this way over their entire circumferential extent so that the faces offsetting

  56 are divided into two parts 56a and 56b, the intersec-

reference 61.

  At the cutting edge 35, the intersection 61 is preferably located radially inward with respect to the shoulder 54, at a distance of

  between one quarter and one half of the thickness of the cheek 26.

  As explained later in this specification, this arrangement allows the formation of chips of desired size by the internal cutting edges. As the inner cut faces 56 of the teeth 20 are stripped so that the desired cutting action is obtained, it is essential. that the surfaces 56 b of the teeth 18 are stripped over a greater extent, preferably corresponding to two to three times the relief of the relief faces 56 of the teeth 20, for example, if the relief faces of the teeth 20 have a clearance of approximately 0 25 mm, the extent of the relief of the trimmed faces 56 b of the teeth 18 must be between about 0.5 and 0.75 mm, at the inner periphery of the cutter.

  The cutting action produced by the tool

  8 to 13 is illustrated more clearly.

  By the views of FIGS. 14 a and 14 b corresponding to a progression. As the detented faces 56, 58 of the successive teeth are stripped in the same manner as in the embodiment already described, the external cutting edges 38 of the successive teeth form the

  chips 64 and 68 indicated in FIGS. 14 a, 14 b,

  with the corresponding chips represented on the

  However, the internal cutting edges of

  successive teeth each cut a chip whose

  is smaller than that of the cutting edge 35

  the trimmed faces 56b of each tooth 18 are stripped of

  12, and 13, the radially outer portion of the cutting edge 35 of each tooth 18 cuts a chip bearing the reference 63 b in Figure 14a, and the radially inner portion of the cutting edges of each tooth. The chip widths 63a and 63b depend on the radial location of the intersection 61 as the radially inner chip 63a has to travel radially a greater distance before reaching a flute 22 of the cutter, it is preferable that the chips 63a have a smaller width than the chips 63b Thus, as shown in Figures 14a and 14b on which the intersection 61 is separated from the shoulder 54 by a distance equal to one third of the thickness of the cheek 26, the

  chip 63a is significantly narrower than chip 63b.

Another variant of the invention is represented

  The cutter shown in this embodiment is generally the same as that of FIGS. 8 to 14 b because the cutter has a single cutting edge (indicated by reference numeral 37) on the portion forming the plays strawberry, but it can have two edges of

  cut as shown in FIGS. 1-7.

  successive teeth have alternately a draft as in the previous embodiments, but in a slightly different manner Thus, the teeth

  are originally formed with indented

  56 and external cali- bration faces 58 which

  cut at a downwardly directed ridge 63 On each tooth 18 (Fig. 16), the outer relief face 58 has a vertical clearance from ridge 63 to the periphery

  external cutter as indicated by reference 58 c.

  The amount of relief of the relief face 58c at the outer periphery of the cutter is within the range indicated above, that is, between 0.075 and

  0.5 mm, depending on the expected chip load, and preferably

  it is between about 0.175 and 0.25 mm.

  Likewise, the internal detachable faces 56 of the teeth 20 (FIG. 15) have a vertical upwardly on the desired length from the ridge 63, radially

  inward as indicated by reference 56 d.

  that successive teeth have a body of this

  In this case, the ridges 63 of all the teeth remain in the same axial and radial position. This arrangement is desirable in the case of small diameter cutters having a small number of teeth. For example, when the cutter has only four teeth, the four crests 63 are in contact

  the room and at the same time begin to attack and de-

  cut the room and thus give less chatter and better accuracy than when only two ridges

  initially come into contact with the piece.

  Figure 16 shows a variant of forma-

  In this variant, the inner cutting edge of each tooth 18 is divided into radially inner and radially outer portions 37a and 37b by means of a recess in the radially inner portion of the inner cutting edge 37.

  grinding of a vertical shoulder to the undersurface

  dull 56 as indicated by reference 37 c As in the

  embodiment of FIGS. 8 to 14 b, the greening

  of the cutting edge part 37a must be higher than

  preferably, two to three times, to the undercut formed at the inner edge 37 of the tooth 20. The location of the shoulder 37c, radially, is determined by

  the factors that determine the location of the intersec-

  61 of the cutter shown in FIGS. 12 and 13, that is to say the relative dimensions of the formed chips.

  by the successive internal cutting edges.

Claims (9)

  Ring milling cutter, characterized in that   it comprises a strawberry body having a side wall   cylindrical shape of a generally circular shape having   a plurality of circumferentially spaced cutting teeth (18, 20) at its lower end, a plurality of flutes (22) rising around the side wall from the lower end, each tooth (18, 20) being connected to the adjacent tooth by a circumferential cheek (26) adjacent the inner periphery of the side wall, the cheeks being juxtaposed radially to the flutes, each flute (22) having anterior and posterior sidewalls   circumferentially spaced and an inner wall dis-   placed circumferentially and which delineates the   outer dial of the cheek, alternating teeth (18) having a radially inner cutting edge formed on the cheek, a groove (42) formed on the cheek and rising from each inner cutting edge and opening radially outwardly in the adjacent flute, all the teeth having a radially outer cutting edge (38),   the radially outer cutting edges (38) being delimited   from the lower end of the side wall   of the adjacent flute, the radial cutting edge   the outer circumference (38) of each of the alternating teeth being offset circumferentially rearwardly with respect to the inner cutting edge (34) of the tooth, taking into account the direction of rotation of the cutter, each tooth (18, 20) having a radially inner relief face (56) which inclines downwardly and radially outwards and a radially outer relief face (58) which inclines downwards and radially inwards, the relief faces   (56, 58) intersecting at a ridge (60), generally   circumference, which at its front end   cut the radially outer cutting edge (38), the   radially external side faces (58) of the alternating teeth   being stripped upwardly relative to the radially outer relief faces of the teeth between the alternating teeth, the radially inner relief face (56) of the intermediate tooth being stripped upwardly from the outer relief faces of the alternating teeth, the the importance of the remains being such that   the inner cutting end of each of the alternate teeth   The cutting edge of the tooth only cuts one chip in a radially internal portion of the tooth and the outer cutting edge of each intermediate tooth cuts a chip only along its radially outer portion, so that the pieces cut off by all cutting edges external   a width less than the radial depth of the gou-   swear. 2 mill according to claim 1, characterized in that the inner and outer cut faces (56, 58)   are stripped in all their radial extent from   that the ridges (60) of the alternating teeth (18) are arranged radially inwardly of the ridges (60) of the intermediate teeth (20).   3 mill according to claim 1, characterized in that the radially outer relief faces (58) of alternating teeth (18) are progressively stripped   more and more from the ridges (60) towards   to the outside, and the internal detented faces of the intermediate teeth are progressively stripped more and more from the ridges radially. towards the inside.   4 mill according to claim 1, characterized in that the intermediate teeth (20) also have internal cutting edges (34) substantially identical to the edges   internal cutting (34) of alternating teeth.   Milling cutter according to Claim 4, characterized in that the radially innermost parts of the inner relief faces (56) of the alternating teeth (18) have a larger upward vertical clearance.   that the relief of the faces of the intermediate teeth   diaries (20) so that the radially outer portion of the inner cutting edge (34) of each alternate tooth (18) and the radially inner portion of the inner cutting edge (34) of each intermediate tooth (20) each cut a chip. Width smaller than that of the inner cutting edge. Milling cutter according to Claim 5, characterized   in that the importance of the remains of the radia-   internally of the internal detachable faces (56) of the alternating teeth (18) at the inner periphery of the cutter   is between 2 and 3 times the skin of the fades de-   internal heels (56) of the intermediate teeth (20) to   the inner periphery of the cutter.   Milling cutter according to claim 5, characterized in that the width of the radially inner portion of the inner cutting edge (34) is between half and three quarters of the width of the inner cutting edge. (34).   Milling cutter according to Claim 5, characterized   in that the radially inner parts of the faces de-   internal heels (56) are placed vertically above   above the radially outer portions of the inner detachable surface (56) and are connected thereto by a circumferential shoulder.   9 mill according to claim 2, characterized in that the inner and outer cut faces (56, 58)   have a body such that the ridges (60) of the teeth   and intermediate (18, 20) are placed radially   at approximately equal distances from the radial axis central flutes.   Milling cutter according to claim 1, characterized in that each of the alternating teeth (18) is formed on its flange (26) with two radially adjacent cutting edges,   namely a cutting edge (34) radially the furthest   and a cutting edge (36) radially between the innermost cutting edge (34) and the outer cutting edge (36), the intermediate cutting edge (36) being circumferentially offset rearwardly from the edge   inner section (34) and towards the front of the outer cutting edge   dull (38), considering the direction of rotation of the cutter, the cheek having a second groove (48) running upwards   from the intermediate cutting edge and opening   outwardly in the adjacent flute (22).