FR2533152A1 - ASSEMBLY OF MACHINE TOOL AND CUTTING TOOL, TOOL FOR CUTTING, TOOL HOLDER, METHOD FOR ADAPTING MACHINE TOOL TO TAKE AND DRIVE TOOL HOLDER WITHOUT TAIL AND METHOD FOR CHANGING TOOL HOLDER - Google Patents

Abstract

THE INVENTION RELATES TO A COUPLING OF WHICH ONE PART IS ASSOCIATED WITH A TOOL OR A TOOL HOLDER AND THE OTHER PART IS ASSOCIATED WITH A TOOL HOLDER OR A MACHINE TOOL SPINDLE. THE COUPLING 46 THEREFORE INCLUDES A PART OF THE SPINDLE 42 OF A MACHINE-TOOL 44 AND A PART OF A TOOL HOLDER 40. THESE TWO PARTS HAVE TEETH 70, 76 AND THEY ARE MADE IN A MANNER TO CENTER AUTOMATICALLY THE TOOL HOLDER ON THE SPINDLE AND TO ELIMINATE ANY CLEARANCE BETWEEN THESE TWO ELEMENTS. APPLICATION DOMAIN ; DIGITAL CONTROL MACHINE-TOOLS, ETC.

Description

The invention relates generally to a method and a

  Advanced device for quick change of used cutting tools

  in a machine tool, and it relates more specifically to

  to a coupling without a tail. The normal and special metal cutting machine tools, currently in use, have driven spindles and tool holders that are designed

  to receive a tool or a tail type tool holder.

  The term "tailed type" in this case refers to any of the commonly known tail devices, for example, the V-flange, the Morse taper, the straight tail, and the like. Tools and tool holders having a shank, for example a V-flange toolholder, have the obvious disadvantage of being bulky and posing problems of exchange of tools between machine tools.

  adapted to the particular dimension of the tail of the holder.

  tool An example of such a situation is that of the spindle driven from a machine tool, adapted to receive

  a tail type tool holder of a particular dimension

  while the surrounding machine tools are

  adapted to receive tool holders having other

  gures or dimensions It is obvious that

  In this case, each machine tool must have its own

  viewing tools or tool holders of the configura-

  particular dimension and dimension to this machine

  Therefore, a CNC machine tool with

  a servant of storage of tools and bearers

  tools, usually containing 30 to 50 tools, alone or with their toolholders and with which a robot is associated

  making changes in cutting tools, can not

  these tools with other machines adapted to receive tools or tool holders whose tails have different dimensions or configurations It can be seen that, when a machine receiving tails of a particular dimension is juxtaposed with a machine receiving tails of a different size, these two machines must have their own supplies

  independent tools and tools.

  Another particular problem with spindle driven machine tools, designed to receive a tail type tool holder, is that the spindle design is affected by the fact that a space must be provided to receive the tail. such a compromise is

  constituted by the over-sizing of the landing located at the

  end of the spindle, this bearing being made to a size

  enough to support the spindle while allowing

  Consequently, all the problems specific to an oversized bearing are placed in a spindle of this type.

  which can be attributed to a very large

  used with the driven spindle is that the maximum speed

  the spindle can be driven for long periods under a predetermined power, is much lower than that of a spindle

  bearing smaller, under the same predetermined power.

  A common problem that has been the subject of

  Many attempts at resolution by operators and machine tool builders are the problem of tail trapping in the bore in which it is fitted Normally, it takes a hole or extreme pressure to release the tail of a machine. A tool or toolholder subjected to repeated taps in a corresponding bore and to the stresses generated by the various extraction methods often presents a problem.

  excessive wear or deterioration.

  Another problem with a tail type tool holder is that when the cutting tool can be

  set relative to the tool holder, it is necessary to

  Special tool for supporting the tool holder so that an accurate measurement of the distance the cutting tool protrudes from this tool holder can be taken Due to the need for a special assembly, it is not uncommon the machine tool operator attempts to adjust by simply resting the tail-type tool holder on its smaller end and measuring the distance from the surface on which it is resting. the tool holder may be dropped and thus the cutting tool may be chipped

  actually constitutes a significant economic waste when

  that we consider the high cost of cutting tools

  used in machining operations of the type in question.

  In general, machine tools are used for precision machining operations and the tendency of the industry is to control these machines more and more often by computer.

  high-speed machining as well as an exchange of

  high speed is a very important goal.

  The possibility, for several machine tools or turrets of machine tools each carrying several cutting tools, to exchange at high speed and the possibility for these same machine tools, to use a common supply of cutting tools having standardized couplings, bring significant savings of time and money 1

  The object of the invention is therefore generally to couple

  fast-changing system which substantially avoids

  The invention also has the following

  a quick-change coupling whose manufacturer

  cation and use are relatively simple and inexpensive, but this coupling is very reliable

  during a long service life, with

multiple uses.

  The invention also relates to a tool and a tool holder which can easily be engaged in

  a support and released from this support without it being necessary

  to apply external forces to them.

  Another object of the invention is a tool or tool holder to which mechanical means can be adapted to pull it

  near the tool support, which has the possibility of

  ability to automatically center when pulled close to the support-, which allows the transmission of a positive drive force through the coupling when used with a driven spindle, which can receive debris accumulated in the coupling, and which can receive torque applied in one direction or

in the other.

  The invention also relates to a coupling

  quick change and a method of using

  this coupling on standardized machine tools,

  putting several of these machine tools

  viewed in cutting tools from a common storage device in which each of the tools of

  stored cup has a single coupling part

  The invention also relates to a coupling in which all the coupling parts are of a standardized configuration and the radial dimension of a coupling part is of no importance provided that

  the coupling has complementary parts.

  The invention also relates to a tool or

  a tool holder comprising means for adapting

  robotics of a rapid change system

  so that the tool or tool holder can perform easily

  movement back and forth between a device

  storage and tool support.

  Another important object of the invention is a tool or tool holder which can be coupled to a tool support and can be decoupled therefrom.

  repeated without the accuracy and efficiency of the

  affected, while maintaining

  the accuracy of alignment of the tool or carrier

  during its multiple reuses, and while minimizing the out-of-round and precessional movements of the cutting tool with respect to a spindle when

  the coupling is used with a rotating spindle.

  The invention therefore relates to a coupling

  fast changing system and method of use thereof.

  According to one aspect of the invention, a quick-change coupling comprises two complementary parts which come into contact by automatically centering and which have a practically zero clearance when a torque is applied to them in a form.

* 2 533152

  preferred embodiment, the engaged parts comprise

  teeth extending approximately radially.

  Another aspect of the invention is the disassembly and replacement of a cutting tool on a carrier in the fastest manner possible, and the removal of multiple independent tool servers.

  associated with different machines.

  The invention will be described in more detail with reference to the accompanying drawings as non-limiting examples and in which:

  FIG. 1 is a longitudinal section through

  a machine tool spindle portion and a prior art tool holder

  FIG. 2 is a longitudinal section through

  a machine tool spindle portion and a tool holder having the coupling according to the invention; FIG. 3 is a section along the line 3-3

  of Figure 2, showing part of a form of embodiment

  Coupling-associated with the spindle Figure 4 is a partial section along

  line 4-4 of Figure 2, showing a form of

  Figure 5 is an elevation of a cutting tool using the principles of the invention; and FIG. 6 is a partial cross-section

  showing the teeth engaged with the training coupling

according to the invention.

  The coupling described herein by way of example is designed to be associated with a driven spindle. However, it should be noted that it is known in the art to mount tools and tool holders on driven slides, the tool or the tool holder not rotating It is also known to mount tools and tool holders on multi-station turrets in which a single tool is presented to a rotating part to perform work on the latter,

  Referring now to the drawings and

  tially in Figure 1, there is shown a

  conventional tool 12 of the type with a tail, called in the industrial

  V-flange type toolholder, and a driven spindle 14 of a machine tool 16 which is adapted to receive the tine type toolholder 12. The latter is one of the preferred tool carriers in the industry. and it comprises a flange 18 having a groove 20 of substantially V-shaped shape intended to engage with the robotics associated with the machine tool 16 The robotics is particularly designed to extract the tool holder 12 from the end of

  the spindle 14 and to make it execute movements

  back-and-forth between a storage position (not shown) and the end of the spindle As shown in FIG. 1, the toolholder 12 of the prior art has an end 22 for receiving a tool (no

  shown) and one end 24 with conical shank 26

  free end of the conical shank 26 has a tapped hole 28 in which can be engaged the traction bar 30 of the machine tool 16 so that this bar pulls and holds the tool holder 12 axially with respect to the end of the spindle The transmission of the torque from the driven spindle 14 to the tool holder 12 is effected at

  two keys (not shown) which

  This is the type of engagement, that is to say with keys and grooves (not shown), which is the standard type for the assembly of this type of assembly. tool holder, allows a relatively large clearance of the tool holder 12 with respect to the pin 14. When a tool holder of the type shown in FIG. 1 is to be used with a machine tool, it

  it is necessary to modify pin 14 so that it pre-

  feels a frustoconical bore 32 which has a dimension

  particular, adapting closely to the particular dimension

  Cylinder 26 of Tail-Type Tool Holder 12 Due to the fact that the end of driven pin 14 is designed to receive shank 24 of a tail-type tool holder 12, it should be noted that the dimension of the bearing 34 and its position are compromised by the fact that this bearing 34 must have a diameter allowing the

$ 25331

  tail 24 of the tool holder 12 to cross it As described below, it is advantageous to limit the size and

the position of the landing.

  FIG. 2 shows a tool holder 40 attached to a driven spindle 42 of a machine tool 44 by means of a coupling 46 embodying the concepts of the invention. The tool holder 40, which is shown in FIG. only by way of example, knowing that any known device for mounting a tool can be used in its place, has a longitudinal axis 50 at one end of which is a bore 52 for receiving the tail of a cutting tool (not shown) and at the other end

  of which is situated a first part 54, arranged radially

  The bore 52 includes locking screws (not shown) for securing the shank of a cutting tool (not shown) relative to this bore. A threaded bore 54, which is centered on the bore longitudinal axis 50 of the tool holder 40, is intended to receive the threaded end 56 of the traction bar 56 of the machine tool 44, the need of which will be explained below. It should also be noted that the particular bar 58 of traction and the means for its attachment to the tool holder 40, for example the tapped bore, are also shown only by way of example and that any known fixing device, used for

  attach a drawbar to a tool or a-holder

  tool, can be used with the invention.

  tool 40 has a common flange 60 having a throat

  62 V-shaped that can be engaged with robotics -

  associated with the machine tool 44 to perform reciprocating movements to the tool holder 40 between a storage area (not shown) and the end of the

  pin 42 As shown in FIG. 2, the outer diameter

  The bearing 64 is substantially smaller than that of the bearing 34 of the device 12 of the prior art. This is intended to show how much the dimensions of the bearings 34 are.

  and 64 may differ from each other when a

  In this case, it appears that no special means must be provided inside the spindle 40 other than the drawbar 58. It should be noted that provision can be made for the use of a bayonet type common mount as well as other

  mechanisms for securing the tool holder close to the former

  Thus, the bearing 64 may be even smaller. As is known in the art, a smaller bearing may rotate at speeds greater than 50 ° C. those of a larger bearing, made of the same material, with less heating, etc. Figures 3 and 4 represent the two parts

  complementary arrangements 66 and 68 of the coupling 46 according to

  Although a particular form of toothing is described herein, there are other forms of toothing to achieve the objectives of the present invention. As shown in FIG. 3, the portion 66 of the coupling 46, associated with the face of the pin 42, has curved teeth 70 which extend from the outer peripheral edge inwards The teeth 70

  are spaced regularly or form a surrounding crown.

  Completely around the circumference of the coupling part 66, each of the curved teeth 70 has two lateral faces, namely an inner face or

  concave 72 and an outer or convex face 74 For each

  that particular form of tooth, there is a point of contact P1 on each of the faces, a spiral angle A and a pressure angle B1 being associated with this point

  (see Figure 6) It can be seen from Figure 4 that the

  The ring formed by the teeth constitutes a reflected image of the crown formed by the teeth and shown in FIG. 3. Each tooth 76 of the coupling portion 68 has a point of contact P 2 on each of its concave faces 78 or convex faces 80. and a spiral angle A 2 and a pressure angle B 2 (see Fig. 6) which are equal to the angles A 1 and B 1 of the associated contact point P 1 of each tooth 70 of the coupling portion 66 shown in Fig. 3 It should be noted at this stage that although other tooth configurations are provided, it is also intended that the crown formed by the teeth is not necessarily continuous all around the faces of the coupling parts. It should also be noted that references to teeth apply, in fact, to all radially arranged elements, allowing

  to achieve the objectives of the present invention.

  Referring back to FIGS. 3 and 4, it will be seen that there are approximately radially oriented teeth 70 and 76 whose dimension increases steadily radially outwardly. The coupling (not shown) of a particular diameter may receive a second coupling portion (not shown) of a different diameter provided that both of these portions have teeth that engage a common diameter to both parts. a pin to which is associated a first part of a

  first diameter can receive tools or

  The tools it has to drive and the diameter of which is different Ideally, the diameter of a coupling portion associated with the spindle is greater than the diameter of the coupling portion associated with the tool

  Although it may be considered as not necessary

  advantageously to have a cutting tool driven by an associated coupling part having a diameter

  significantly larger than the diameter of the

  In addition to the spindle, it should be noted that the transmitted torque can be determined by the speed of the spindle and the amount of

cut with a substrate.

  FIG. 6 represents the meshing of the teeth and 76 of the two coupling parts 66 and 68 and shows a zone 82 of clearance situated at the bottom of the teeth 70 and 76, this zone being able to receive debris

  that can accumulate on the face of the teeth

  debris cans that can prevent complete grip of the teeth 70 and 76 can thus be pushed into the space 82 of clearance by the teeth when they enter

  It should be noted that zone 82 of clearance

  is not critical to establishing or breaking off

  The presence of an open clearance zone 82 as shown in FIG. 6 is not necessarily desirable when there is a problem of cooling fluid flow. due to communications between the clearance zones 82 and openings (not shown) in the spindle and in the tool or

  tool holder to allow the flow of cooling fluid

dissement.

  FIG. 5 represents a cutting tool 84

  read in one piece with a first part (68)

  of the coupling (46) The cutting tool also has

  the characteristics necessary to facilitate the

  latching with the robotics (not shown> associated with the machine tool and allowing this cutting tool 84 to be subjected to movements back and forth between a storage device (not shown) and the pin 42 of the machine As indicated by the distance D, it is easy to see that the overall length of this device 84 in one piece can be substantially less than that of a tool-holder assembly and cutting tool which necessarily comprises a structure allowing fixing the cutting tool to a tool holder By

  therefore, by removing the bored portion of the

  tool and the associated structure, as well as the part of a cutting tool to cooperate with the bored portion (not shown), the length can be substantially reduced.

  overall D of the cutting tool made in one piece.

  The obvious advantage of such a configuration is greater flexibility as regards the size of the parts being machined when the area in which the cutting tool is to be used is of reduced dimensions. in the present specification, cutting tools are all common types of cutting tools, for example, blade-type cutting tools, carbide cutting tools, etc. In a variant, the coupling parts 66 and 68, shown in FIGS. 3 and 4, can be integrated at the end of the driven pin 42 or the support

  tool (not shown), and tool 84 or

  In addition, it should be noted that each of the parts 66 and 68 of the coupling 46 can be made separately, then attached to the spindle 42 or the tool holder (not shown), and to the tool. 84 or the tool holder 40, respectively When coupling parts 66 and 68 are made as separate parts, then each of the parts must be fixed so as to be centered on the axis of rotation of the pin 42 or the tool support (not shown) and on the axis of rotation of the tool 84 or the tool holder 40, respectively As it is obvious to those skilled in the art 2 the fixing of separate parts can be made by any suitable means (not shown), for example by bolts, by welding, etc. It is therefore easy to realize that by making the parts of the coupling form

  of separate parts, we get an adapter.

  Although a ring of teeth arranged substantially radially is shown on each of the parts 66 and 68 of the coupling, it is planned to be able to use several bands (not shown) of teeth on each part of the coupling. Each of these bands can be

  arranged radially with respect to the other bands

  that tapes of teeth of substantially incur-

  are used, each band can be

  that these teeth are curved in a predetermined direction

  terminated by using bands of teeth that extend in different predetermined directions, to

  different radial distances, we can see that

  tools of different diameters may be selectively designed to engage, in a selected manner, with a particular band.

R 533152 '

  If a particular tool or tool holder can not be gripped by the inability of its coupling part to engage with the coupling part of the support or the spindle. can affect the selectivity with which cutting tools can be mounted on a particular spindle In cases where right-hand and left-hand cutters are used, it is obviously undesirable to set up a cutting tool incorrect because, when a cutting tool is driven in the wrong direction, significant stresses and friction appear and the cutting tool

can be destroyed.

  A particular advantage of using a tool 84 or a tool holder 40 of the type described is that the user can advantageously make a measurement of the axial distance over which the cutting tool protrudes by simply placing the tool 84. or the tool holder 40

  on a flat surface, the teeth 76 of the coupling portion

  apply against this surface, and by measuring the flat surface to the point of the tool

  cutting edge farthest from the support surface.

  One of the main advantages of mating

  according to the invention as described lies in the

  machine tools which have been particularly

  adapted to receive tool holders of the type Tail Sou-

  wind, machine tools that have been adapted to tools

  and tail type carriers are no longer universal.

  stool, because of their adaptation to receive a

  particular tail end A secondary benefit

  both the use of the coupling according to the invention is that the machine tool and / or the robotic that serves it have more to apply the significant force required, either by typing or otherwise, to clear a tool or a

  tail type tool holder in the spindle.

  When we want to standardize various machines-

  adapted tools, the modification of the end of the driven spindle or the support can be carried out either by machining the complementary coupling part, or by 25331 e fixing an adapter comprising the toothed part

  As a result, provision may be made for

  tool with a large number of tools or tool holders, which, in the case of machine tools serviced by robots and with numerical control, avoids having to use separate tool holders, carrying tools or tool holders adapted in particular to each machine. As is well known to specialists in

  machine tools, the maximum speed at which a machine

  tool works is limited by the maximum speed that

  can support the bearing housed in the pin More

  In fact, a numerically controlled machine tool capable of working for many hours and sometimes - for several days in a row without the assistance of an operator - may overheat the bearing if the spindle is driven too quickly. High Knowing that the bearing is the limiting factor of the speed on which a machine tool can work, it is understood that a particular machine tool, adapted to receive a toolholder type large tail has a much lower maximum speed That is, when a cutting tool that can work at high speed is used with a machine tool adapted to large shanks. it is obvious that the cutting tool can not be used at a speed greater than the maximum allowed by the machine.

  tool This is actually a situation reflecting a lack of efficiency, which can be avoided by adapting the concept of the invention to the machine tool By allowing the use of a smallest bearing that allows the spindle to turn at higher speeds, we see that the machine tool can use much more flexible cutting tools designed to work at a

high rotation speed.

  To perform the change of a tool or a tool holder of the type described herein, the robotics associated with the machine tool can engage with the means provided on the tool or tool holder and the For example, to change a cutting tool mounted on a spindle or moving support, the machine tool is usually slowed down or stopped, allowing the robot to take the tool or tool holder and move it around. while it is released from the drawbar Once the drawbar has released the tool or tool holder, the tool can be moved to the associated position in the storage device. then position the next cutting tool to be used close to the end of the spindle, the pulling bar then engaging with the tool or tool holder and attaching to it It should be noted that when the traction bay pulls the tool or the tool holder towards At the end of the spindle, the teeth of the two parts of the coupling engage and automatically center the tool or tool holder, thereby bringing the axis of rotation of the cutting tool into alignment with the axis. It is clear that a single toolholder can be used and that the robotics can control the movements of the cutting tools towards this servant.

  in the opposite direction and can supply several machines-

  tools because of the possibility of exchange offered

  by the particular universal coupling according to the invention.

  In use, a machine tool having a spindle and a support equipped with the coupling according to

  the invention can engage with and support a carrier

  tool or cutting tool, and in the case of the spindle,

  train it, this cutting tool having a complementary part

  Coupling To engage the tool or tool holder, the coupling parts are juxtaposed so that the teeth engage, and a drawbar or other element is engaged in such a way that firmly engage the teeth of the coupling parts The main advantage of the

  The present invention is obtained when the parts of

  The coupling very precisely positions the axis of rotation of the tool relative to the axis of rotation of the spindle or support and, because of the larger surface area due

  at the curvature of the teeth, we obtain a better distribution

  charge and a greater torque capacity. It should be noted that the parts of the coupling

  can be used as an automatic coupling

  engageable by the use of a spring or other member exerting a predetermined restoring force, such as

  that parts of the mating are released under the

  The ease with which a tool or toolholder can be uncoupled from a spindle or a support is easily apparent because, when the means for holding the two parts of the coupling together are released, the coupling separates practically. Although a particular form of toothing has been described and although it should be noted that the configuration of the toothing has been described in U.S. Patent No. 4,307,797, and for the purposes of this invention

  description, the teeth are described as extending

  approximately radially and are arranged approximately radially, other forms of teeth, for example teeth extending quite radially, as well as elements arranged radially, making a firm engagement and automatic centering, are provided as being

  encompassed in the present invention.

  It goes without saying that many modifications can

  may be made to the device described and shown

  without departing from the scope of the invention.

Claims (33)

  1 Set of a machine tool (44) and a   cutting tool for use with the machine   tool, characterized in that it comprises a quick-change coupling (46) for fixing the cutting tool to a support member (42) carried by the machine tool, said coupling having a first portion (68)   associated with the cutting tool and a second part (66) associated with   the support element, the first and second par-   comprising substantially radially arranged means   mented and designed to mesh directly, in a complementary   and which can be disengaged from one another, these means being intended to automatically center the tool   cutting with respect to the support member.   2 assembly according to claim 1, characterized in that the first part is made in one piece with the cutting tool.   3 assembly according to one of claims 1 and 2,   characterized in that the second part is made of a   single piece with the support element.   Assembly according to claim 1, characterized in that the means arranged approximately radially comprise a plurality of teeth (70, 76) extending approximately radially. Assembly according to Claim 1, characterized   in that the support member is a driven pin (42).   6 The assembly of claim 5, characterized in that it comprises a fastening element (58) for pulling said first portion axially to engage with the second portion on the spindle and thereby center automatically, about simultaneously, the tool   cut in relation to the spindle in order to establish a transmission   stiffness for the cutting tool through the coupling while limiting the clearance to practically zero inside the coupling.   7 assembly according to claim 1, characterized   in that it comprises a tool holder (40) designed to support   removably remove the cutting tool, the first   part being made in one piece with this holder tool.   8 assembly according to one of claims 1   and 7, characterized in that the means arranged approximately radially on the first portion and the second portion each comprise a plurality of curved teeth (70, 76), each of said teeth having inner concave faces (72, 78) and outer convex (74, 80), each tooth being configured such that any point of contact (Pl or P 2) along one of the inner and outer faces has a spiral angle (A 1 or A 2) and   a pressure angle (B: or B 2) equal to the angles corresponding to   of the corresponding point of contact located along the corresponding outer convex and inner concave of the outer part.   9 assembly according to claim 8, characterized in that the width of each curved tooth varies from   the inner part of the tooth towards its outer part.   Assembly according to claim 7, characterized in that the tool holder comprises means for adjusting the cutting tool which it supports relative to it in order to adjust the distance of the outer part of the tool relative to the spindle, a precise fit that can be achieved by resting the tool holder by the first part against a flat surface and measuring the distance from the outer portion of this tool on this surface.   11 assembly according to claim 8, characterized in that a foot (82) is formed between the adjacent teeth   of each pair, each foot being sized to accommodate see debris.   12 assembly according to claim 1, characterized in that the support member is a driven pin (42) carried by a bearing (64) whose inner diameter is   sufficient to allow the passage of a fastener tion (58).   Assembly according to claim 1, characterized in that the coupling forms an adapter, means for connecting the first part of the coupling to the cutting tool and means for connecting the second part of the coupling. coupling to the support member so that a machine tool adapted to receive cutting tools and tool holders of a particular configuration can be modified by said coupling to to be universal.   Assembly according to Claim 1, characterized in that the maximum dimension of the means arranged approximately radially, associated with the first part, is equal to or smaller than the maximum dimension of the arranged means.   about radially, associated with the second part.   Assembly according to claim 1, characterized in that it comprises means (60, 62) associated with the cutting tool to allow a maneuvering device to perform an engagement to bring closer and away   the cutting tool of the support element.   16 cutting tool forming part of the assembly of claim 1, characterized in that it comprises a tool body having a first element for performing a cutting work on a workpiece, a second element (54) arranged axially compared to the first   element to engage with an element (58) for fixing   associated with the support member for pulling the tool axially toward said support member, a third member (68) concentrically disposed with respect to   second element in order to engage with a com-   element (66), arranged concentrically and associated with the support element, the third element having means arranged approximately radially and allowing a self-centering coupling of the tool with the complementary element, so that an axial force traction, applied by the second element, causes the engagement of the third element with the tool and the automatic centering of the latter relative to the element   complementary carried by the support member.   17 cutting tool according to claim 16, characterized in that it comprises means for 253, Isz-2   firmly attach the third element to the tool body.   18 cutting tool according to claim 16, characterized in that the third element is disposed near a plane substantially perpendicular to the longitudinal axis (50) of the body of the tool. Cutting tool according to claim 16, characterized in that the second element comprises a tapped hole (54) centered on the longitudinal axis of the tool body. Cutting tool according to claim 16, characterized in that the tool body has a threaded hole (54) and that the fastening element is a   pull bar (58) designed to be arranged axially   relative to the support element in order to engage   in the tapped hole and thus pull the tool towards the support.   Cutting tool according to one of the claims   16 and 19, characterized in that the third element and the complementary element each comprise several curved teeth (70, 76).   22 cutting tool according to claim 21,   characterized in that each of the teeth has a face.   concave interior (72 or 78) and a convex outer surface (74 or 80) configured such that any point of contact (Pl or P 2) along one of the inner and outer faces of one of the third element and the complementary element has a spiral angle (A 1 or A 2) and a pressure angle (B 1 or B 2)   equal to those of the corresponding contact point located -   along the respective outer and inner faces of   the other of the said third element and the said element   mentary. Cutting tool according to claim 16, characterized in that the support element is a spindle conducted (42).   24 Tool holder for the tool according to claim 16, characterized in that it comprises a body (40) comprising a first element (52) intended to receive a portion of a tool, a second element intended to secure removably said part of the tool inside the first element, a third element   (54) axially disposed relative to the body of the holder   tool to engage with a fastener (58)   associated with a support member (42) attached to the machine-   tool for pulling said tool holder axially towards the element   support, a fourth element (68) arranged   third element to engage with a complementary member (66), concentrically arranged and associated with the support member, the fourth member having means extending approximately radially, which allows coupling with   automatic centering of the tool holder with the additional element   that an axial force of traction, exerted   third element, triggers the activation of the   third element and the automatic centering of the tool holder with the complementary element carried by the support element.   Tool holder according to claim 24, characterized   in that the second element is adapted to allow adjustment of a cutting tool carried by the tool holder so that a precise adjustment of the distance over which the tool protrudes axially from the tool holder can be measured at the of the fourth element which is then juxtaposed to a flat surface, the measurement being made of said   surface to the outer point of the cutting tool.   Tool holder according to claim 24, characterized   in that it includes means designed to secure   the fourth element to the tool holder.   Tool holder according to claim 24, characterized   in that the body of the tool holder has a longitudinal axis (50), the first element having a bore (52) in which the portion of the tool is received, this bore being centered on the longitudinal axis and opening   at one end of the body.   28 Tool holder according to claim 27, characterized   in that the fourth element is disposed close to   mite of a plane substantially perpendicular to the axis   longitudinal axis at the other end of the body of the tool.   Tool holder according to claim 28, characterized   characterized in that the second element comprises at least one screw oriented angularly towards the periphery of the bore and intersecting this periphery so as to apply   against the part of the tool received in the bore.   Tool holder according to claim 24, characterized   characterized in that the fastening means comprise a drawbar (58) designed to be arranged axially   relative to the support member.   Tool holder-according to one of the claims   24 and 29, characterized in that the fourth element and the complementary element each comprise a plurality of curved teeth (70, 76).   32, a tool holder according to claim 9, characterized   in that each of the teeth has an integral face   concave surface (72, 78) and a convex outer surface (74, 80> configured such that any point of contact (Pl or P 2), located along the inner and outer faces of one of the fourth element and of the complementary element has a spiral angle (A 1 or A 2) and a pressure angle (B 1 or B 2) equal to those of the point   corresponding contact located along the corresponding faces   outside and inside of the other of the fourth   element and said complementary element.   33 Tool holder according to claim 24, which is   characterized in that it comprises a fifth element (60, 62) designed to engage with an external mechanism of   handling to transport the tool holder.   Tool holder according to one of the claims   24 and 32, characterized in that the support element is a driven spindle (42).   A method for adapting an assembly according to claim 1 so as to be able to drive a tool carrier (40) without a tail, characterized in that it consists in adapting the spindle (42) of the machine tool so that it comprises a coupling member (66> being removably and automatically centering engageable with a toothed complementary coupling element (68)   placed on a tool or tool holder, to use a   interlocking mechanism (58) for pulling a tool or a tool carrier having a toothed element towards the spindle complementary coupling.   Process according to claim 35, characterized in that the adaptation step consists in machining the face   the spindle to form a toothed coupling element is lying.   Method according to claim 35, characterized in that the adaptation step consists of fixing a concentrically applied annular coupling element on the face of the brooch.   38. Method according to claim 37, characterized in that the fastening consists in bolting the element coupling on the spindle.   The method of claim 35, characterized   in that it consists in producing each of the teeth (70, 76) of the coupling element so that it has a concave inner face (72, 78> and a convex outer face (74, 80) to establish and drafting angles (Aj, A 2) and pressure (Bj, B) which are substantially <B equal for the inner and outer faces of each tooth.   Process according to claim 35, characterized   it consists in setting up the bearing (64) holding the spindle in an optimal position and dimensioning the bearing to raise as much as possible the precision with which the machine tool makes a tool work.   engaged using mating.   41 Method for changing a tool holder according to   any of claims 24 to 34, characterized in   it consists in taking the tool holder to be replaced using a mobile device, in releasing the tool holder from the spindle (42), in moving the tool holder to be replaced from its position of close use the spindle, to bring a replacement tool holder near the   pin, place the replacement tool holder for   engaging the engagement with an element (58) for pulling the tool towards the spindle, engaging the element for pulling the tool holder towards the spindle, pulling the tool holder toward the spindle to thereby establish rigid mission with the toolholder, this transmission   having virtually no play and being performed by   of complementary teeth (70, 76) extending radially, and to center the tool holder by means of these   teeth under the action of the element intended to pull the door tool to the spindle. c