WO2016176068A1

WO2016176068A1 - Machine for hot marking parts of revolution and marking method using such a machine

Info

Publication number: WO2016176068A1
Application number: PCT/US2016/028049
Authority: WO
Inventors: Florent Demange
Original assignee: Illinois Tool Works Inc.
Priority date: 2015-04-29
Filing date: 2016-04-18
Publication date: 2016-11-03
Also published as: FR3035612B1; EP3288762B1; FR3035612A1; PL3288762T3; EP3288762A1

Abstract

The machine as claimed in the invention is a machine for hot marking parts of revolution (100). It comprises a heat punch (92), first means for relative movement between the heat punch and a part along a first axis, second means for bringing each part to be marked across from the punch, those means being able to rotate the part around its axis of revolution (A100), third means for relative movement between the part (100) and the punch (92) along a second axis perpendicular to the first axis and the axis of revolution of the part during the marking, and fourth means (74, 94, 78) for relative movement between the part (100) and the punch (92) along a third axis (Y6) perpendicular to the second axis. The machine further comprises fifth means (90, 70, 69) for orienting a marking surface (S92) of the punch (92) around a fourth axis parallel to the second axis and, in a complementary manner, to a contact generatrix of the part, the axis of revolution (A100) of the part being perpendicular to the first axis during the marking, and sixth means (96) for rotating the punch (92) around a fifth axis (Z96) perpendicular to the third (Y6) and fourth axes.

Description

MACHINE FOR HOT MARKING PARTS OF REVOLUTION AND MARKING METHOD

USING SUCH A MACHINE

The invention relates to a machine for hot marking parts of revolution, and a method for marking a part which is at least partly frustoconical, and uses such a machine.

In the field of hot marking of parts of revolution, it is known to move a heat punch to the outer surface of a part to be marked, such as a cosmetics bottle or mascara case, by interposing a marking ribbon between the part and the punch, thus making it possible to create a pattern on the outer surface of the part.

A hot marking machine is known from EP-B-2 236 296 comprising a heat punch which is mobile vertically, in order to exert a hot pressure force on a marking ribbon which is positioned on the outer surface of a part to be marked. The part to be marked is retained between points on a cradle which is mounted on a carriage mobile in translation on a plane perpendicular to the direction of movement of the heat punch. This cradle comprises a rotary mandrel and a tailstock between which the part to be marked is retained. The mandrel rotates the part around its axis of revolution.

In order to mark the part correctly, the cradle is programmed such that the part rolls without slipping on the marking surface of the punch. However, a frustoconical object which roles without slipping on a flat surface describes a circular trajectory, the center of rotation of which corresponds to the center of convergence of the generatrix of the object, i.e. to the center of conicity. Thus, in the case when the part to be marked is at least partly frustoconical, the cradle then describes a circular trajectory in order to reproduce a contact of rolling without slipping. In addition, the generatrix of the outer surface of the part to be marked is not parallel to its axis of revolution. The machine therefore comprises means for inclining the cradle in order to position the generatrix of the part to be marked parallel to the marking surface of the punch. The part is therefore not positioned naturally, and its trajectory is complex to program. In addition, the marking rate is relatively low.

US-B-8 474 376 also discloses a device for silk screen printing of conical objects. This device comprises a frame, a screen which is mobile relative to the frame and bears meshing with a printing pattern, and a scraper which is supported by the frame, and presses the meshing of the screen against the conical object in order to apply the printing pattern on the object. The device comprises a motor to drive the screen in rotation around an axis perpendicular to the screen, and two carriages to move the screen on a plane perpendicular to the axis of rotation of the screen. The device also comprises a cradle for receipt of the part to be printed. This cradle comprises a gear motor assembly to drive the conical object in rotation around its axis of revolution. This gear motor assembly is designed to pivot in order to orient the generatrix of the conical object parallel to the printing screen. This patent does not relate to a hot marking machine, and the object is not positioned naturally, i.e. with its axis of revolution horizontal.

It is these disadvantages which the invention is intended more particularly to eliminate, by proposing a hot marking machine wherein the trajectory of the object to be marked is simplified, wherein the object does not need to be inclined during the marking, and which has an improved marking rate.

For this purpose, the invention relates to a machine for hot marking of parts of revolution, this machine comprising:

- a heat punch;

- first means for relative movement between the heat punch and a part along a first axis;

- second means for bringing each part to be marked across from the punch, those means being able to rotate the part around its axis of revolution;

- third means for relative movement between the part and the punch along a second axis perpendicular to the first axis and the axis of revolution of the part during the marking; and

- fourth means for relative movement between the part and the punch along a third axis perpendicular to the second axis.

The machine additionally comprises:

- fifth means for orienting a marking surface of the punch around a fourth axis parallel to the second axis and, in a complementary manner, to a generatrix of the part, the axis of revolution of the part being perpendicular to the first axis during the marking; and

- sixth means for rotating the punch around a fifth axis perpendicular to the third and fourth axes.

Thanks to the invention, the trajectory of the object to be marked is simplified, since the movement of relative rotation between the object and the punch, which, in EP-B- 2 236 296, is obtained by moving the object, can be carried out by moving the heat punch. The invention makes it possible for example to mark an object which turns only around its axis of revolution, since the machine comprises means for applying to the punch a movement of rotation, which, within the context of the object, corresponds to a movement of rolling without slipping. This movement is broken down in order to adjust the radius of curvature easily and equip the machine with non-voluminous means for movement. In addition, it is not necessary to incline the part to be marked, since it is the punch which is oriented in a manner complementary to the generatrix of the object. The part to be marked thus retains a natural position in which the axis of revolution is perpendicular to the first axis.

According to advantageous but non-compulsory aspects of the invention, the marking machine can incorporate one or a plurality of the following characteristics, taken in any technically permissible combination:

- The means for bringing form the third means and comprise at least two arms mounted pivoting around a shared axis parallel to the third axis and each bearing at least one support member for the part, and means for driving each arm independently in rotation around the shared axis.

- The support member is able to rotate the part around its axis of revolution.

- The machine comprises means for adjusting the position of the punch along the first axis based on the movement of the part along that axis.

- The fourth means are configured to move the punch and include a guideway, which is mounted sliding parallel to the third axis, a roller inserted inside the guideway, which is connected to the punch such that it rolls inside the guideway and moves the latter parallel to the third axis when the punch pivots around the first axis, and a system with connecting rods to move the punch along the third axis while using the movement of the guideway.

- The fourth means are configured to move the punch and include a carriage translatably connected to the punch along the third axis, an electric motor that is mounted on the carriage and that is able to rotate a pulley around an axis parallel to the first axis, a belt cooperating with the pulley to move the carriage along the third axis, and means for guiding the translation of the carriage.

- The punch is rotatably connected around the fourth axis with a table maintained between two flanges and the fifth means comprise: at least two pins secured to the table, which each cross through a curved guide opening formed in each flange, and an adjusting knob, able to move the pins in the guide openings.

- The sixth means include an electric motor.

- The machine further includes means for bringing a marking ribbon between the part and the heat punch.

The invention also relates to a method for hot marking a part of revolution that is at least partially frustoconical, this method being implemented using a machine as previously described and comprising successive steps consisting of:

a) from a loading station, mounting a part of revolution on an object-holder;

b) bringing the part across from the marking punch;

c) pivoting the part around its axis of revolution; d) during the marking, applying at least one rotational movement of the punch around the first axis to reproduce the relative rotational movement between the part and the punch that corresponds to a rolling contact without slipping; and

e) bringing the part toward an unloading station.

The invention and others of its advantages will become more apparent in the light of the following description of four embodiments of a hot marking machine and of methods according to their principle, provided purely by way of example and with reference to the drawings in which:

- figure 1 is a view in perspective of a marking machine according to the invention; - figure 2 is a view on an enlarged scale of the rectangle I I in figure 1 ;

- figure 3 is a view in perspective of a marking assembly belonging to the machine in figures 1 and 2;

- figure 4 is a view in perspective of part of the marking assembly in figure 3, on which a marking ribbon is also represented;

- figures 5 to 9 represent successively, in a view from below and during the marking, the successive positions of a heat punch belonging to the marking assembly in figures 3 and 4 relative to the part to be marked;

- figure 10 is a schematic view illustrating the movement of rotation of a part during the marking and the corresponding movement of the punch;

- figure 1 1 is a diagram representing a mechanism for movement of the heat punch along a horizontal axis according to the rotation applied around a vertical axis, for a machine according to a second embodiment of the invention;

- figures 12 to 16 are views similar to figures 5 to 9 for a machine according to a third embodiment of the invention; and

- figures 17 to 21 are views similar to figure 5 to 9 for a machine according to a fourth embodiment of the invention.

Figures 1 to 4 represent a machine 2 for hot marking parts of revolution. In particular, the machine 2 is designed to create a pattern on the outer surface of a part 100 which is at least partly frustoconical, such as a mascara bottle or a cosmetics case.

The hot marking machine 2 comprises a fixed frame 4 in the form of a cabinet, a marking assembly 6, and means 8 for bringing each part to be marked 100 across from a heat punch 92 which belongs to the marking assembly 6. The heat punch 92 comprises a flat rectangular marking surface S92.

The machine 2 comprises means 50 for relative movement between the heat punch 92 and a part to be marked 100 according to a vertical axis Z6. In the example, it is the marking assembly 6, comprising the heat punch 92, which is mobile along the axis Z6 relative to the part to be marked 100. The means 50 thus make it possible to move the assembly 6 relative to the fixed frame 4. They can be seen only in figure 3, and comprise an electric motor which is accommodated in a case, and can drive a pulley 52 in rotation around a vertical axis. The pulley 52 cooperates with a belt 54, in order to drive the assembly 6 in translation according to the vertical axis Z6, via a ball screw not shown.

As can be seen in figure 2, the bringing means 8 comprises two independent arms 80 and 82 which are mobile in rotation around a common axis Y8 which is perpendicular to the axis Z6. The machine 2 comprises means for driving each arm 80 and 82 independently in rotation around the shared axis Y8, as represented by the arrow R3 in figure 10. The bringing means are therefore similar to those described in patent US-B- 8 443 861 . The arms 80 and 82 are independent, i.e. they can rotate at different speeds around the axis Y8. In particular, this makes it possible to make one arm rotate faster than the other.

Each arm 80 or 82 comprises at its two ends a support member 84, which can be better known as an object-holder, since it supports the part to be marked 100. Each support member 84 delimits a bore 86 for the positioning of a mandrel, not represented. The part to be marked 100 is mounted around the mandrel and is driven in rotation by the latter around an axis parallel to the axis of rotation Y8 of the arms 80 and 82. Each support member 84 thus comprises means, not represented, for driving the mandrel in rotation around its axis, and making the part 100 rotate around its axis of revolution A100, as represented by the arrow R2 in figure 10. The axis A100 can be seen in particular in figure 4.

The machine comprises a loading station, not represented, at which the parts to be marked 100 are automatically mounted on the mandrels of the arms 80 and 82. This loading station is not represented in the figures, but in practice is secured on bars 10 which are arranged on the left of the arms 80 and 82, in the front view of the marking machine 2. Similarly, the hot marking machine 2 comprises an unloading station, which is not represented in the figures, but which in practice is secured on the bars 12 arranged on the right of the arms 80 and 82 in the front view of the machine. Once they have been marked, the parts 100 are discharged at this unloading station.

The machine 2 comprises a chassis 56 which is integral with the frame 4, and a plate 58 which is mobile along the axis Z6 relative to the chassis 56, and on the front of which there are secured two blocks 55 for connection of pneumatic supply pipes and electric cables. The marking assembly 6, which can be better known as the "marking head", is represented only in figure 4. It comprises a plate 62 which is designed to be secured on the front face of the plate 58. Thus, the marking assembly 6 is mounted in a manner which is detachable relative to the remainder of the machine 2. Two flanges 68 with a rectangular cross-section are secured on the plate 62, and extend towards the front parallel to an axis Y6. In this document, the front thus designates a direction parallel to the axis Y6 which faces towards an observer positioned opposite the machine 2. The two flanges 68 extend on both sides of a support table 69. The table 69 is retained between the flanges 68 by means of screws, not represented, which pass through an oblong opening 72 provided in each flange 68. Specifically, the oblong openings 72 extend parallel to the axis Y6.

The table 69 supports a carriage 74 which is mobile in translation relative to the table 69, along the axis Y6. The machine 2 thus comprises means for driving the carriage 74 in translation along the axis Y6. These means comprise a motor 94 which is mounted directly on the carriage 74, such that it is moved integrally with the carriage 74 along the axis Y6. By means of an angle return device, the motor 94 drives a pulley 78 with a vertical axis of rotation, which is arranged below the carriage 74, i.e. between the carriage 74 and the table 69. This pulley 78 drives a belt, not represented, which is attached to the carriage 74. The rotation of the pulley 78 in one direction or the other gives rise to the movement of the carriage 74 respectively forwards or rearwards parallel to the axis Y6.

The heat punch 92 is arranged below the table 69. It is connected in translation to the carriage 74, i.e. it is moved jointly with the carriage 74 along the axis Y6. In addition, the carriage 74 is guided in translation by means of two guideways 76 which extend parallel to the axis Y6, and are arranged on the sides of the carriage 74. A single one of these guideways 76 can be seen in figure 3.

The carriage 74 delimits a recess for the passage of a second electric motor 96. This electric motor 96 can drive the punch 92 in rotation around an axis Z96. The table 69 and the carriage 74 are immobile in rotation around the axis Z96. The axis Z96 intersects the marking surface S92. Preferably, the axis Z96 passes through the center of the marking surface S92.

The marking machine 2 implements a marking method by means of a marking ribbon 102 which can be seen only in figure 4. It thus comprises means for bringing and guiding a marking ribbon 102 between the heat punch 92 and a part to be marked 100. These means comprise a bar 98 which is secured on the heat punch 92, and supports an unwinder 106 and a plurality of rollers 104 and 1 08 for guiding of the ribbon 102. In figure 4, the ribbon 102 is moved from right to left, i.e. going from the unwinder 106 in the direction of the rollers 104. This marking ribbon 102 is interposed between the marking surface S92 of the punch 92 and the part to be marked 100 during the marking, and follows all the movements of the punch 92. The ribbon 102 permits printing of a pattern on the part 100.

During the marking, the parts to be marked 100 which are fitted around the rotary mandrels of the object-holders 84 maintain a natural position in which their axis of revolution A100 is perpendicular to the axis Z6, i.e. the parts 100 are not inclined. Thus, for frustoconical parts, it is necessary to orient the marking surface S92 of the punch 92 in a manner which is complementary to a contact generatrix G 100 of the part 100. The generatrix G 100 corresponds to the segment of the object 100 which is in contact with the punch 92 during the marking. The marking machine 2 thus comprises means for orienting the marking surface S92 of the punch 92 around an axis X92 which is perpendicular to the axis Z96 and to the axis Y6. Advantageously, the axis X92 and the axis Z96 intersect. In practice, the marking surface S92 of the punch 92 is oriented such that the generatrix G 100 of the object 100 is contained on the plane of the marking surface S92 during the marking. In other words, the angle of inclination of the marking surface S92 relative to a horizontal plane corresponds to the angle between the generatrix G 100 and the axis of revolution A100.

The means for adjustment of the orientation of the punch 92 around the axis X92 include a manual adjusting knob 90 and two curved openings 70 provided in each flange 68. The center of curvature of the openings 70 is arranged on the axis X92. Two pins, not represented, which are integral with the table 69, are inserted in the two curved openings 70 in each flange 68. The punch 92 is connected in rotation around the axis X92 with the table 69. The rotation of the knob 90 gives rise to the movement of the pins in the curved openings 70, which has the effect of orienting the table 69, the carriage 74, the ribbon 102 and the punch 92 jointly around the axis X92. The openings 70 thus act as guides for the pins.

During the orientation of the punch 92, the screws for retention of the table 69 also pivot jointly with the table 69 and the punch 92. In order to facilitate the machining, the openings 72 are not curved. On the other hand, they are wider than the width of the body of the screws, in order to allow the screws which pass through them to have a circular trajectory during the orientation of the punch 92 relative to the outer surface of the part to be marked.

When the punch is not oriented around the axis X92, i.e. when the marking surface S92 is parallel to the ground, the axes Y6 and Y8 and the axes Z6 and Z96 are parallel in pairs. However, the axes Z96, X92 and Y6 remain perpendicular in pairs, irrespective of the orientation of the punch 92. Hereinafter, a method is described for marking of a part by means of the machine 2. In order to obtain neat marking of a part 100, the contact between the part 100 and the marking surface S92 must be in rolling contact without slipping. However, as can be seen in figures 5 to 9, a frustoconical object which rolls without slipping on a flat surface describes a circular trajectory, the center of rotation of which corresponds to the center of convergence C of the outer surface of the object, i.e. to the center of conicity. This center C can be seen only in figure 9, for the sake of clarity of the drawings. The center C is situated at the intersection between the line which extends the generatrix G100 and the axis of revolution A100.

A contact of rolling without slipping of the object on the marking surface is obtained by applying a movement of relative rotation between the object and the punch around a vertical axis which passes via the center of conicity of the object. In patent EP-B- 2 236 296, this movement is obtained by making the object rotate relative to the punch, whereas the marking method according to the present invention consists rather of moving the punch 92, in order to reproduce a movement of relative rotation between the punch 92 and the object 100, which, within the framework of the object, is rotation around the vertical axis which passes via the center of conicity of the object. This movement of rotation is obtained by combining two movements of the punch 92, i.e. a first movement of rotation around the axis Z96, and a second movement in translation along the axis Y6. In addition, the trajectory of the punch 92 is programmed according to the degree of conicity of the object to be marked.

In particular, the marking machine 2 comprises an electronic control unit 200 which is represented only in figure 3, and is configured to establish automatically a set trajectory for the punch 92 according to the degree of conicity of the object to be marked. For this purpose, the electronic control unit 200 deduces the degree of conicity of the object according to the degree of orientation of the punch 92, which is previously adjusted manually by an operator. The electronic control unit thus calculates the radius of curvature R92 of the trajectory of the punch 92 within the framework of the object. The electronic control unit then breaks down this movement of rotation into movement along the axis Y6 and rotation around the axis Z96.

The marking method according to the invention which is designed to mark a pattern on a part which is at least partly frustoconical can be broken down into a plurality of steps described hereinafter.

A first step consists of loading a part to be marked 100 on an object-holder 84, from the loading station. The arm 80 or 82 on which the part to be marked is mounted then pivots around the axis Y8 in order to bring the object 100 across from the heat punch 92. The object 100 which is brought across from the punch 92 comes into contact with the marking surface S92 of the punch 92. This contact is not direct, since the ribbon 102 is interposed between the punch 92 and the object 100.

A second step consists of moving the punch 92, in order to reproduce within the framework of the object a circular movement around the vertical axis which passes via the center of conicity of the object 100. This movement of relative rotation between the object 100 and the punch 92 allows the object 100 to roll without slipping on the marking surface S92 of the punch 92.

In addition, as can be seen in figure 10, since the part to be marked 100 describes a circular movement which is centered on the axis Y8, each part to be marked 100 is moved firstly in the vertical direction, i.e. parallel to the axis Z6, and secondly parallel to the axis X92. The marking punch 92 is thus moved vertically according to the change of altitude of the part 100, as the rotation of the arm 80 or 82 takes place, i.e. according to the coordinates along the axis Z6 of the part 100. More particularly, when the part 100 comes across from the punch 92, i.e. on the arc of a circle which extends between the points I and J in figure 10, the punch 92 rises, so as not to prevent the rotation of the object 100, as represented by the arrow F4. On the other hand, when the object has gone beyond the point J, which is the highest point of the trajectory of the object 100, the punch 92 descends in order to keep the contact with the object 100, as represented by the arrow F5. The punch 92 descends until the object 100 has carried out a complete turn around its axis of revolution A100, i.e. as far as the point K in figure 10.

The vertical movement of the punch 92 associated with the rotation of the object 100 is programmed in the aforementioned electronic control unit, i.e. the electronic control unit 200 forms means for adjusting the position of the punch 92 along the axis Z6 according to the movement of the marked part 100.

Once the object 100 has been marked, it is taken in a third step to the unloading station, where it is unloaded. The aforementioned steps are implemented for each arm 80 and 82, and iteratively.

The aforementioned second step is described with reference to figures 5 to 9, in which the ribbon 102 is not represented, for the sake of clarity of the drawings..

In figures 5 to 9, S100 represents the developed form of the outer surface of the part to be marked 100. This developed form represents the contact surface between the part 100 and the marking surface S92 when the part 100 is rolled by a complete turn around its axis of revolution A100. This surface S100 is delimited between two arcs of a circle C1 and C2 with the same center, i.e. the center of conicity C of the object 100, but with different radii of curvature, the arc of a circle C1 being further from the center of conicity C than the arc of a circle C2. S100' represents the surface of the punch 92 which has been in contact with the object 100. This surface S100' is hatched in figures 5 to 9, in order to make it easier to visualize.

In figure 5, the object 100 comes into contact with the marking surface of the punch 92. The surface S100' then has a zero area.

As the object 100 is moved along the axis X92, i.e. from the left to the right in figures 5 to 9, the punch pivots around the axis Z96 in the anticlockwise direction in a view from below and is moved from the rear forwards parallel to the axis Y6. By this means, the surface of the punch S100' which is in contact with the object 100 during the marking corresponds exactly to a part of the rolling surface of the object 100 on the marking surface S92. When the object 100 has performed a complete turn around its axis of revolution A100, i.e. in the configuration in figure 9, the surface S100' corresponds to the developed form of the outer surface of the part to be marked.

Definitively, in order to obtain a contact of rolling without slipping between the object to be marked and the punch, it is necessary to have rotation of the object 100 around its axis of revolution A100, a movement of relative rotation between the punch 92 and the object around the axis Z96, a movement of relative translation between the punch and the object along the axis Z6, a movement of relative translation between the punch and the object along the axis Y6, and a movement of relative translation between the punch and the object along an axis which is perpendicular to the axes Y6 and Z6. In the example of the machine represented in figures 1 to 4, the aforementioned first and final movements are applied to the object 100, whereas all the other movements are applied to the punch 92. Nevertheless, as variants, it is possible to transpose the movements applied to the punch 92 to the object 1 00, and conversely. These variants are described in greater detail hereinafter.

As a variant not represented, other means for bringing the part to be marked 100 across from the punch can be envisaged. For example, the parts to be marked can be mounted in turn between points on a cradle, as envisaged in EP-B-2 236 296.

As a variant represented in figure 1 1 , applicable to the first embodiment, the movement of translation of the heat punch 92 along the axis Y6 is not carried out by means of the electric motor 94, but is induced directly by the movement of rotation around the axis Z96. For this purpose, the machine comprises a guideway 200, which is mounted such as to slide according to a direction parallel to the axis Y6, and a roller 202, which is inserted inside the guideway 200 and is connected to the punch 92 by a connecting rod 204. The connecting rod 204 and the roller 202 are articulated. The roller 202 rolls inside the guideway 200, and moves the latter parallel to the axis Y6 when the punch 92 pivots around the axis Z96. The machine also comprises a system S of connecting rods, in order to move the punch 92 along the axis Y6 using the movement of the guideway 200. This system S with crankshafts comprises four crankshafts 206, 208, 210 and 212, which are articulated on one another in series, between firstly the guideway 200, and secondly a fixed part of the machine. The system S additionally comprises a rigid assembly formed by two bars 214 and 218 which are integral with one another, and form an obtuse angle between one another. This rigid assembly forms a mobile slide parallel to the axis Y6, and comprises a first end which is mounted in an articulated manner on the connecting rod 208, and a second end which is mounted in an articulated manner on the punch 92.

Thus, a movement of rotation R1 of the punch 92 around the axis Z96 is transformed into a movement F1 of translation along the axis Y6 by cooperation of the elements 200, 202 and 204. This movement F1 is then transposed by means of the system S with connecting rods to the slide, according to the arrow F2. Finally, the punch 92 is driven in translation together with the slide 216, as represented by the arrow F3.

According to a variant represented in figures 12 to 16, the relative movement between the punch 92 and the object 100 along the axis Y6 is obtained by moving the object 100 along the axis Y6. The punch 92 is thus immobile in translation along the axis Y6. The means for bringing the object 100 across from the punch 92 are then configured to move the object 100 along an axis which is parallel to the axis Y6. Thus, the heat punch 92 is mobile only in rotation around the axis Z96 and in translation along this axis. The machine designed for implementation of the marking method described in figures 12 to 16 is not represented in the figures.

In this case, the position of the punch 92 along the vertical axis Z6 is adjusted according to the movement of the object 100 parallel to the axis Y6, in order to take into account the fact that the generatrix of the object G100, i.e. the segment of contact between the object 100 and the punch 92 of the object 100 is inclined relative to the axis of revolution of the object.

Also in this case, the machine can comprise means for bringing a plurality of marking ribbons in order to produce patterns with imbricated colors.

According to another variant represented in figures 17 to 21 , the only movement applied to the part to be marked 100 is a movement of rotation around its axis of revolution A100. The part 100 is thus immobile in the reference X92, Y6, Z6. The machine which is designed for implementation of the marking method described in figure 17 to 21 is not represented in the figures. In this machine, all the other movements are applied to the heat punch 92 in order to make the object 100 roll without slipping on the marking surface S92. In particular, the machine which is designed for the implementation of the marking method described in figures 17 to 21 comprises means for driving the punch 92 in translation along an axis perpendicular to the axes Y6 and Z6.

According to another variant not represented, the hot marking machine 2 comprises a number of bearing arms different from two.

According to another variant not represented, the punch 92 is immobile in the vertical direction. The movement of relative rotation between the punch 92 and the part to be marked 100 in the vertical direction is thus obtained by moving the part to be marked 100 vertically relative to the punch 92. The means for bringing the part across from the punch are thus designed to move each object parallel to the axis Z6.

The technical characteristics of the variants and embodiments envisaged above can be combined with one another to generate new embodiments of the invention.

Claims

1 . A machine (2) for hot marking parts of revolution (100), that machine comprising: a heat punch (92),

- first means (50, 52, 54) for relative movement between the heat punch and a part along a first axis (Z6),

second means (8) for bringing each part to be marked across from the punch, those means being able to rotate the part around its axis of revolution (A100),

- third means (8) for relative movement between the part (100) and the punch (92) along a second axis perpendicular to the first axis (Z6) and the axis of revolution (A100) of the part during the marking, and

- fourth means (74, 94, 78, 76) for relative movement between the part (100) and the punch (92) along a third axis (Y6) perpendicular to the second axis, characterized in that the machine further comprises:

- fifth means (90, 70, 69) for orienting a marking surface (S92) of the punch (92) around a fourth axis (X92) parallel to the second axis and, in a complementary manner, to a contact generatrix (G100) of the part, the axis (A100) of revolution of the part being perpendicular to the first axis (Z6) during the marking, and sixth means (96) for rotating the punch (92) around a fifth axis (Z96) perpendicular to the third (Y6) and fourth (X92) axes.

2. The machine as claimed in claim 1 , characterized in that the second means (8) form the third means and comprise:

- at least two arms (80, 82) mounted pivoting around a shared axis (Y8) parallel to the third axis (Y6) and each bearing at least one support member (84) for the part, and

- means for driving each arm (80, 82) independently in rotation around the shared axis.

3. The machine as claimed in claim 2, characterized in that the support member (84) is able to rotate the part (100) around its axis of revolution (A100).

4. The machine as claimed in claim 2 or 3, characterized in that the machine comprises means for adjusting the position of the punch (92) along the first axis (Z6) based on the movement of the part (100) along that axis.

5. The machine as claimed in one of the preceding claims, characterized in that the fourth means are configured to move the punch (92) and include:

- a guideway (200), which is mounted sliding parallel to the third axis (Y6),

- a roller (202) inserted inside the guideway, which is connected to the punch such that it rolls inside the guideway and moves the latter parallel to the third axis when the punch pivots around the first axis (Z6), and

- a system (S) with connecting rods (206-214) to move the punch along the third axis while using the movement of the guideway.

6. The machine as claimed in any one of claims 1 to 4, characterized in that the fourth means are configured to move the punch (92) and include:

- a carriage (74) translatably connected to the punch (92) along the third axis (Y6),

- an electric motor (94) that is mounted on the carriage and that is able to rotate a pulley (78) around an axis parallel to the first axis (Z6),

- a belt cooperating with the pulley (78) to move the carriage along the third axis (Y6), and

- means (76) for guiding the translation of the carriage.

7. The machine as claimed in one of the preceding claims, characterized in that the punch (92) is rotatably connected around the fourth axis (X92) with a table (69) maintained between two flanges (68) and in that the fifth means (90, 70, 69) comprise:

- at least two pins secured to the table (69), which each cross through a curved guide opening (70) formed in each flange (68), and

- an adjusting knob (90), able to move the pins in the guide openings (70).

8. The machine as claimed in one of the preceding claims, characterized in that the sixth means (96) include an electric motor (96).

9. The machine as claimed in one of the preceding claims, characterized in that the machine further includes means (98, 104, 106, 108) for bringing a marking ribbon (102) between the part (100) and the heat punch (92).

10. A method for hot marking a part of revolution (100) that is at least partially frustoconical, this method being implemented using a machine (2) as claimed in one of the preceding claims and comprising successive steps consisting of:

a) from a loading station, mounting a part of revolution on an object-holder (84), b) bringing the part across from the marking punch (92),

c) pivoting the part (100) around its axis of revolution (A100),

d) during the marking, applying at least one rotational movement of the punch (92) around the first axis (Z6) to reproduce the relative rotational movement between the part and the punch that corresponds to a rolling contact without slipping, and e) bringing the part toward an unloading station.