EP2671676A1 - System for finishing a part made of a plurality of materials - Google Patents

Abstract

The system (21) has accommodating devices (23, 23') containing an abrasive medium, and a support device (25) comprising a securing unit (22) for securing a part i.e. bezel (1), to be finished. A moving unit (27) moves the part closer against the medium. A relative movement unit (29) moves the part relative to the accommodating devices according to required satin finish lines. The accommodating devices comprise tanks (24, 24') containing the medium in powder form, where each tank is elastically formed to adapt powder level in the tank relative to force imposed by the moving unit. The part consists of two materials having different hardness. The abrasive medium is selected from silica and/or corundum and/or pumice and/or diamond and/or nitrides and/or carbides and/or alumina. The hard material is selected from a group consisting of aluminum, titanium, zirconium or silicon based oxide, carbide or nitride.

Description

Field of the invention

The invention relates to a system for finishing a workpiece formed of several materials and, more particularly, to such a workpiece, each material of which has a different hardness.

Background of the invention

It is known to satin elements to improve their visual rendering. However, it is difficult when the piece is formed of several materials to properly satinize only part of the piece. Currently, it is necessary to bring a rotating brush and manually satin the desired parts. This causes a cost too high and a finish that is too heterogeneous from one satin part to another of the room.

Summary of the invention

The object of the present invention is to overcome all or part of the disadvantages mentioned above by proposing a finishing system of a part made of several materials that allows the selective satinization of one or more of the materials with great homogeneity.

For this purpose, the invention relates to a system for finishing a workpiece comprising at least two materials of different hardnesses, the system comprising at least one receiving device serving as a container for abrasive means, a support device comprising fastening means of the workpiece, characterized in that the system further comprises means for bringing the workpiece closer to the abrasive means, relative displacement means of the workpiece relative to the receiving device according to the desired saturation lines characterized in that each receiving device comprises a vessel containing said abrasive means in powder form and in that the vessel is resilient in order to adapt the level of powder in the vessel relative to the force imposed by the means of bringing together.

It is therefore understood that the directions of the satin lines are directly obtained by the relative displacement means of the finishing system. Therefore, the time required to satin the areas is always the same regardless of the number of areas to be satin on the same piece and the lines are perfectly homogeneous with respect to each other.

• les particules comportent un diamètre compris entre 0,3 mm et 1 mm;
• les moyens abrasifs sont formés à partir de silice et/ou de corindon et/ou de ponce et/ou de diamant et/ou de nitrures et/ou de carbures et/ou d'alumine ;
• chaque dispositif de réception comporte en outre des moyens de vibration de la cuve permettant de renouveler la couche supérieure des moyens abrasifs quand les moyens de rapprochement écartent la pièce des moyens abrasifs ;
• les moyens de rapprochement comportent un actionneur permettant de presser la pièce contre les moyens abrasifs ;
• l'actionneur des moyens de rapprochement exerce une force comprise entre 1 Kg et 5 Kg ;
• les moyens de déplacement relatif comportent un moteur permettant à la pièce d'imprimer un mouvement de va-et-vient contre les moyens abrasifs selon lesdites raies de satinage souhaitées ;
• le mouvement de va-et-vient contre les moyens abrasifs est linéaire ou concentrique ;
• le système comprend au moins deux dispositifs de réception afin de renouveler lesdits moyens abrasifs d'un des dispositifs de réception quand l'autre dispositif est utilisé pour finir ladite pièce ;
• lesdits au moins deux dispositifs sont montés sur un plateau déplaçables à l'aide d'un chariot afin de sélectivement positionner un desdits au moins deux dispositifs en vis-à-vis du dispositif de support.

According to other advantageous features of the invention:

• the particles have a diameter of between 0.3 mm and 1 mm;
• the abrasive means are formed from silica and / or corundum and / or pumice and / or diamond and / or nitrides and / or carbides and / or alumina;
• each receiving device further comprises means for vibrating the tank for renewing the upper layer of the abrasive means when the means for bringing the part away from the abrasive means;
• the bringing means comprise an actuator for pressing the workpiece against the abrasive means;
• the actuator of the approximation means exerts a force of between 1 Kg and 5 Kg;
• the relative displacement means comprise a motor allowing the part to print a reciprocating movement against the abrasive means according to said desired saturation lines;
• the movement back and forth against the abrasive means is linear or concentric;
• the system comprises at least two receiving devices for renewing said abrasive means of one of the receiving devices when the other device is used to finish said part;
• said at least two devices are slidably mounted on a tray to selectively position one of said at least two devices opposite the support device.

Brief description of the drawings

• la figure 1 est un exemple d'application d'une pièce formée de plusieurs matériaux ;
• la figure 2 est une représentation en coupe d'un dispositif de réception selon l'invention ;
• la figure 3 est une représentation en perspective d'un système de finissage selon l'invention ;
• la figure 4 est une représentation en perspective d'un dispositif de support selon l'invention.

Other particularities and advantages will emerge clearly from the description which is given hereinafter, by way of indication and in no way limiting, with reference to the appended drawings, in which:

• the figure 1 is an example of application of a piece made of several materials;
• the figure 2 is a sectional representation of a receiving device according to the invention;
• the figure 3 is a perspective representation of a finishing system according to the invention;
• the figure 4 is a perspective representation of a support device according to the invention.

Detailed Description of the Preferred Embodiments

The piece formed of several materials according to the invention can in particular integrate or compose indifferently all or part of the dressing of a timepiece. Thus, it could form all or part of a case, a bracelet, a bezel, a dial, an ice, a pusher and / or a crown. It is also possible to integrate or compose pieces made of several materials belonging to a watch movement such as, for example, a bridge and / or a platinum and / or an oscillating weight.

In the example shown in figure 1 the explanation of the invention will be given from an annular body 3 having inlaid decorations 5, 7, 9, 11, 13 forming the graduations of a telescope 1. Thus, the telescope 1 comprises a body 3 made of a first material which is encrusted with at least one decoration 5, 7, 9, 11, 13 in one or more other materials. The bezel 1 is intended to form a very wear-resistant part whose visual quality is improved in particular in terms of contrast.

As illustrated in figure 1 it can be seen that each decoration may, advantageously according to the invention, be of any shape, such as, for example, a geometrical figure 7, 9, 11, an alphanumeric character 5 or even a phosphorescent indicator 13.

The body 3 is preferably made of a first hard material, that is to say with a hardness greater than 800 Hv, such as for example a ceramic. The first material may, for example, comprise an oxide, a carbide or a nitride based on aluminum, titanium, zirconium or silicon to form all or part of the body 3. Of course, other materials hard are possible.

Preferably according to the invention, the second material or the other materials used for decorations 5, 7, 9, 11, 13 are of lower hardness than the first material. Thus, advantageously, the invention relates to a finishing system 21 of such a part 1, each material has a different hardness. The system 21 advantageously makes it possible to satin the material or materials having the lowest hardness without modifying the appearance of the material having the highest hardness. Thus, without limitation, other less hard materials may be a composite ceramic, a glass, an enamel, a metal or a metal alloy.

However, it is understood that the hardest material could be one or those of decorations 5, 7, 9, 11, 13 and not that of the body 3 as will be explained below.

According to the invention, the finishing system 21 comprises at least one receiving device 23, 23 'serving as a container for abrasive means and a support device comprising means for fixation of the piece 1. In addition, the system 21 further comprises means 27 for bringing the piece 1 closer to said abrasive means 20 and means 29 for relative movement of the piece 1 with respect to the receiving device 23 according to the strips desired satin finish.

Advantageously according to the invention, the means 27 of approaching and the means 29 relative displacement can be mounted indifferently on the support device 25 or on the receiving device 23. In the example of the figure 3 , the connecting means 27 and the relative displacement means 29 are mounted on the support device 25.

Each receiving device 23, 23 'comprises a tank 24, 24' containing said abrasive means 20 in the form of powder in which the means 27 of approach at least partially plunge the piece 1.

Preferably, the powder abrasive means 20 is formed by particles whose hardness is greater than the (x) material (s) to be satin but less than the (x) material (s) to leave intact. Preferably, the piece 1 will be polished prior to its finishing using the system 21. It is understood that only part of the part 1 will have its modified surface state, that is to say that at least one materials used will not be modified on the surface. By way of example, the particles, whose diameter may be between 0.3 mm and 1 mm, may be formed from silica and / or corundum and / or pumice and / or diamond and / or nitrides and / or carbides and / or alumina.

As explained above, the means 27 of approximation exerts a force sufficient to immerse a portion of the workpiece 1 in the powder of abrasive means 20. Preferably according to the invention, the tank 24, 24 'is resilient in order to adapt at the level of powder in the tank 24, 24 'relative to the force imposed by the means 27 of approximation. The tank 24, 24 'thus exerts a counter-force B intended to press the powder 20 between the tank 24, 24' and the piece 1. Indeed, during the development of the 21 system, it was shown that a rigid tank allowed the powder to move and cover the part 1 by making imperfect finishing. It is therefore understood that, thanks to the tub 24, 24 'elastic, the powder 20, advantageously, does not cover the entire part 1 even under the constraint of the means 27 bringing together ensuring optimum finishing.

In addition, at each finishing, the particles of abrasive means 20 having rubbed on the part 1 become dull. Therefore, advantageously according to the invention, each receiving device 23, 23 'further comprises means 26, 26' of vibration of the tank 24, 24 'for renewing the upper layer of the powder when the means 27 bringing together part 1 of the abrasive means 20. In fact, the upper layers of particles present in the tank 24, 24 'having participated in the finishing have seen their diameter decrease. Therefore, during vibration C, these smaller particles are mechanically displaced to the bottom of the tank 24, 24 '. Thus, it is understood that the surface powder is renewed by particles of larger diameters, that is to say, not blunted.

In the example shown in figure 4 , the means 22 for fixing the support device 25 comprise a fastener 30 formed of three movable fingers approximating to hold a workpiece 1. This fastener 30 is mechanically connected to the means 27 for bringing it together. Preferably, the means 27 for bringing together comprise an actuator 28 making it possible to press the piece 1 against the abrasive means 20 in the direction D in order to provide a force A against the abrasive means 20 necessary for finishing. Preferably, the actuator 28 exerts a force of between 1 and 5 kg.

Finally, in the example shown in figure 2 , the relative displacement means 29 comprise a motor 31, which may belong to the actuator 28 of the means 27 for approximation, allowing the workpiece to print a movement E back and forth against the abrasive means 20 according to said desired satin lines.

For an annular part 1 presented as an example to figures 1 and 4 , the satin lines will be preferentially concentric. The movement E of back and forth will then be an alternation of trigonometric and retrograde rotations. Indeed, during the development of the system 21, it has been shown that a simple rotation made the finishing less homogeneous. Such a reciprocating movement E can be exerted on an amplitude of between 5 and 20 mm depending on the size of the part 1. During the development, it has been shown, in the case of a rotary movement E of va and-come, an amplitude between 20 and 40 degrees gives a high homogeneity of satin.

In view of the explanations above, it is understood that the desired saturation lines can also be linear. In this case, the motor of the relative displacement means will induce a movement E back and forth in translation.

A finishing process according to the invention therefore follows the following steps. At first, a part 1 comprising at least two materials of different hardness is manufactured and then at least one of the faces is polished. In a second step, the part 1 is mounted on the fastener 30 of the fastening means 22, the polished surface being intended to come into contact with the abrasive means 20. In a third step, the means 27 of approaching are activated according to the movement D until the piece 1 touches the abrasive means 20.

In a fourth step, the means 27 of approximation exerts a force between the part 1 and the abrasive means 20 necessary for the satin finish. Advantageously according to the invention, the abrasive means 20 in the form of powder are blocked by this force and the spring against force B of the tank 24. From the third or fourth time, the relative displacement means 29 are also activated according to the invention. the E movement back and forth. The fourth beat can take a few seconds to get a satisfactory satin finish.

In a fifth step, the means 27 of approximation and the relative displacement means 29 are deactivated in order to move the piece 1 away from the abrasive means 20. At the same time, the vibration means 26 are activated in order to renew the upper layer of the abrasive means 20 in powder form. The fifth time may take a few seconds to obtain a satisfactory renewal.

After the fifth beat, a new cycle is started with a new piece or with the same piece, that is starting from the first beat or from the third beat.

In the example visible at figure 3 it will be noted that the finishing system 21 comprises two receiving devices 23, 23 '. This embodiment is preferred to gain productivity. Indeed, as visible at the figure 3 while a workpiece 1 is worked with a first receiving device 23, the second receiving device 23 'can be renewed in abrasive means. Thus, the new cycle explained above is initiated using the carriage 33 which will move the plate 32 so that the second device 23 'is positioned vis-à-vis the support device 25.

It is thus understood that it is conceivable to finish the pieces 1 by applying to each piece 1 consecutively the abrasive means of the type different from at least two receiving devices 23, 23 'and / or at least two systems 21.

It is advantageously understood according to the system 21 of the invention that the time required to satin the areas is always the same regardless of the number of areas to be satin on the same room. In addition, the lines are perfectly homogeneous with respect to each other whether curved or linear.

Of course, the present invention is not limited to the illustrated example but is susceptible of various variations and modifications that will occur to those skilled in the art. In particular, it is also possible to finish pieces 1 of very varied shapes, that is to say not limited to an annular shape presented to the Figures 1 and 2 , both for an element of a timepiece and outside of watchmaking as for tableware, jewelery or jewelry.

In addition, each system 21 may comprise more or fewer receiving devices 23, 23 'and / or more or fewer support devices 25 without these embodiments being outside the scope of the invention. By way of example, the same finishing system 21 could comprise two support devices 25 enabling two pieces to be finished simultaneously and six receiving devices 23, 23 'with three different types of abrasive means 20 used mounted on a single displaceable plate 32. by a trolley 33.

Finally, depending on the materials used for the part, the abrasive means must be adapted. They can not be limited to the materials cited in this description.

Claims (12)

System (21) for finishing a workpiece (1) comprising at least two materials of different hardnesses, the system (21) comprising at least one receiving device (23, 23 ') containing abrasive means (20), a device (25) support comprising means (22) for fixing the workpiece (1), means (27) for bringing the workpiece (1) against the abrasive means (20) and means (29) for relative movement of the workpiece (1). the part (1) with respect to the receiving device (23) according to the desired saturation lines, characterized in that each receiving device (23, 23 ') comprises a tank (24, 24') containing said abrasive means (20) in the form of powder and in that the tank (24, 24 ') is elastic in order to adapt the level of powder in the tank (24, 24') relative to the force imposed by the means (27) of approach. System (21) according to the preceding claim, characterized in that the particles have a diameter of between 0.3 mm and 1 mm. System (21) according to one of the preceding claims, characterized in that the abrasive means (20) are formed from silica and / or corundum and / or pumice and / or diamond and / or nitrides and / or or carbides and / or alumina. System (21) according to one of the preceding claims, characterized in that each receiving device (23, 23 ') further comprises means (26, 26') for vibrating the tank (24, 24 ') allowing renewing the upper layer of the abrasive means (20) when the means (27) of approaching part of the gap (1) abrasive means (20). System (21) according to one of the preceding claims, characterized in that the connecting means (27) comprise a actuator (28) for pressing the workpiece (1) against the abrasive means (20). System (21) according to the preceding claim, characterized in that the actuator (28) of the means (27) of approximation exerts a force of between 1 Kg and 5 Kg. System (21) according to one of the preceding claims, characterized in that the means (29) of relative movement comprise a motor (31) allowing the workpiece (1) to print a movement (E) of va-et- comes against the abrasive means (20) according to said desired saturation lines. System (21) according to one of the preceding claims, characterized in that the movement (E) back and forth against the abrasive means (20) is linear. System (21) according to one of claims 1 to 10, characterized in that the movement (E) back and forth against the abrasive means (20) is concentric. System (21) according to one of the preceding claims, characterized in that it comprises at least two receiving devices (23, 23 ') for renewing said abrasive means of one of the receiving devices when the other device is used to finish said piece. System (21) according to the preceding claim, characterized in that said at least two devices (23, 23 ') are mounted on a plate (32) movable by means of a carriage (33) in order to selectively position one of said at least two devices vis-à-vis the device (25) support. System (21) according to one of the preceding claims, characterized in that the piece (1) is an element of the cladding of a timepiece.

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