EP1689569B1 - Method for piercing optical glasses with the aid of a digitally controlled drill and device for carrying out said method . - Google Patents

Abstract

The method involves fixing a lens in a position where a reference point of the lens corresponds to a punch (33), by moving the lens in a plane perpendicular to an axis of a piercing tool (15). The tool is brought closer to the lens. The punch is retracted to disengage a support zone of the lens. The tool is controlled by a numerically controlled piercing machine (12) to pierce the lens, by using the reference point as zero point. An independent claim is also included for a device for implementing a method of piercing the ophthalmic lens.

Description

FIELD OF THE INVENTION

The present invention relates to the drilling of optical glasses for the realization of glasses called pierced glasses and without surrounding frame.

BACKGROUND OF THE INVENTION

Long ago there have been wired frame structures on which eyeglass lenses are fixed by bolting systems or the like, the lenses being then not surrounded by the frame. Each spectacle lens then has one or more holes and / or a notch opening at the nasal area and the temporal area of said lens. To secure each glass thus pierced to a wired hinged frame portion, various mechanical fastening means have been proposed, the most common of which are bolting.

There is the problem of making the different machining of the nasal and temporal areas of spectacle lenses as simple and precise as possible.

The document JP-A-8 155 945 discloses an optical lens piercing unit for making two through-holes in the vicinity of opposite edges of each spectacle lens. This document describes a machining assembly with a very complex structure and high cost. The document JP-A-8 155 806 also discloses a drilling assembly with oscillating glass supports. For the drilling of particular holes in optical glasses, reference may also be made to the documents WO-A-00 / 68,729 describing a drilling assembly for making oblong through holes, and the document WO-A-99 / 37,449 describing a drilling assembly adapted to the machining of blind holes made in the thickness of the glass.

The drilling assemblies described in the aforementioned documents, however, are of complex structure and high cost.

We can also refer to the document FR-A-2,800,172 describing a method of drilling optical glasses using computer assistance to associate drilling planes with a given virtual glass template.

The document EP-A-0 739 683 describes a set of drilling glasses glasses for making holes and notches in the glasses. There is a double XY slide positionable on a steerable ruler mounted on a platen. When machining glasses, the glass supports are moved relative to the piercing tool in a horizontal plane without rotation.

The document WO 00/67974 discloses a drilling apparatus for optical glasses with a complete system for supporting two drills. Each support is mounted to slide in horizontal translation, which makes it possible to produce, by two successive machining operations, a bore and a notch, or two holes, along a rectilinear path.

In general, if a numerically controlled drill is used, the marking of the machining points is always done from an indexation set on the center of the glass, said center being considered as a zero point of a coordinate system forming a center of two coordinate axes in a horizontal plane. When the vertical axis of the drilling tool is brought vertical to the center of the glass, the machine is calibrated, so that any new XY movement allows the tool to be accurately positioned for drilling at a given point in the glass. . However, to perform such drilling, it assumes that the CNC drill has in memory all forms of glasses to be machined, since each glass must be equipped with holes and / or notches in the vicinity of its nasal area and its temporal area according to precise distances from free edges of the glass. As a result, this technique is de facto limited to very conventional forms of glasses, in particular circular, oval, square or rectangular, whose profile has been previously stored. The operator must then each time search the memory for the corresponding glass profile, then search also in the memory for the desired machining pattern for the chosen glass. This represents important constraints for operators, not to mention the risk of errors in the case where a profile has been incorrectly stored. As a result, digital drills used for drilling spectacle lenses are heavy and bulky machines, which are reserved for large assembly workshops.

There is therefore a need for a mechanical drill less cumbersome and more manageable, that opticians could use in their shop or assembly shop.

It has recently been proposed a hand-operated mechanical drill specially developed to make open slots on optical glasses, and possibly also holes. As such, please refer to the document FR-A-2,826,599 . This document describes a drill whose piercing tool is manually movable in a vertical direction. In the associated method of implementation, it is intended to position a glass in a plane substantially perpendicular to the axis of rotation of the piercing tool, so that the relevant edge of the glass is against the piercing tool , then immobile, at a point of tangency previously identified on the glass, and the glass is immobilized in this position. Only then is the piercing tool rotated, and the glass is moved relative to the rotating piercing tool according to a movement in a horizontal plane in accordance with a rotation. around a fixed point distinct from the trace of the axis of the drilling tool, the amplitude of the rotation corresponding to the length of the notch opening to be machined. Then, the piercing tool is moved away from the glass by manually raising said tool along its axis.

Such a mechanical drill is an interesting tool, but the approach used is not applicable to CNC drills.

• un procédé de perçage de verres optiques pour la réalisation de lunettes dites à verres percés et sans monture entourante, au moyen d'une perceuse à commande numérique ayant un support d'outil (21) déplaçable en translation suivant trois directions de coordonnées X,Y,Z, l'outil de perçage associé (51) étant entraîné en rotation et déplaçable en translation suivant son axe (voir figure 2) qui est parallèle à l'une desdites directions, ledit procédé comportant les étapes successives suivantes:
  1. a) on positionne et on immobilise un verre (L);
  2. b) l'outil de perçage (51) est alors rapproché du verre (L) toujours immobilisé,
  3. c) l'outil de perçage (51) est commandé pour réaliser des séquences d'usinage préprogrammées.

The document JP-A-08 155 945 is considered to represent the most relevant state of the art for independent claim 1 and implicitly shows the use of the device described in this document (references in parentheses apply to this document):

• a method of drilling optical glasses for producing glasses said to pierced lenses and without surrounding frame, by means of a numerically controlled drill having a tool support (21) displaceable in translation in three directions of X, Y coordinates , Z, the associated drilling tool (51) being rotated and displaceable in translation along its axis (see figure 2 ) which is parallel to one of said directions, said method comprising the following successive steps:
  1. a) positioning and immobilizing a glass (L);
  2. b) the piercing tool (51) is then brought closer to the glass (L) still immobilized,
  3. c) the piercing tool (51) is controlled to perform preprogrammed machining sequences.

• un dispositif pour la mise en oeuvre d'un procédé de perçage, comprenant:
• une platine (21) essentiellement horizontale portant une perceuse à commande numérique (26) ayant un support d'outil (28) en surplomb deplaçable en translation suivant deux directions de coordonnées X et Y et dont l'outil de perçage (29) est entraîné en rotation et déplaçable en translation suivant son axe qui reste essentiellement vertical et
• un support de verre (20) agencé pour maintenir un verre dans un plan essentiellement horizontal, ledit support reposant sur un plan solidaire de la platine (21) précitée et étant immobilisable en position par rapport audit plan.

The document US2003 / 0097741 A1 is considered to be the most relevant state of the art for independent claim 9 and described (references in parentheses apply to this document):

• a device for carrying out a drilling method, comprising:
• a substantially horizontal platen (21) carrying a numerically controlled drill (26) having an overhanging tool support (28) displaceable in translation along two X and Y coordinate directions and having the drilling tool (29) driven therefrom in rotation and movable in translation along its axis which remains essentially vertical and
• a glass support (20) arranged to hold a glass in a substantially horizontal plane, said support resting on a plane integral with the plate (21) above and being immobilisable in position relative to said plane.

OBJECT OF THE INVENTION

The present invention aims to design a drilling technique optical glasses do not have the aforementioned drawbacks and limitations, while using a numerically controlled drill.

The object of the invention is thus to design a piercing method and a device for implementing said method which are both simple and easy to implement, while guaranteeing optimum precision in producing the desired holes or notches, and this without being limited to any particular form of glasses.

GENERAL DEFINITION OF THE INVENTION

1. a) on positionne un verre, en le déplaçant dans un plan sensiblement perpendiculaire à l'axe de l'outil de perçage, par rapport à un pointeau repère, dont la position dans ledit plan est connue de la perceuse à commande numérique, jusqu'à amener un point de référence préalablement marqué sur un bord du verre en appui contre le pointeau repère, après quoi ledit verre est immobilisé dans cette position ;
2. b) l'outil de perçage est alors rapproché du verre toujours immobilisé, et le pointeau repère est escamoté pour dégager la zone d'appui du verre ;
3. c) l'outil de perçage est commandé pour réaliser des séquences d'usinage préprogrammées, en utilisant la position du point de référence du verre comme point zéro desdites séquences.

This problem is solved according to the invention by means of a method of drilling optical glasses for the realization of glasses called drilled glasses and without surrounding frame, by means of a numerically controlled drill with a tool support movable in translation. along three coordinate directions X, Y, Z, the associated drilling tool being rotated and displaceable in translation along its axis which is parallel to one of said directions, comprising the following successive steps:

1. a) positioning a glass, moving it in a plane substantially perpendicular to the axis of the drilling tool, relative to a reference pin, whose position in said plane is known to the control drill numerically, to bring a reference point previously marked on an edge of the glass bearing against the reference needle, after which said glass is immobilized in this position;
2. b) the piercing tool is then brought closer to the glass still immobilized, and the reference needle is retracted to clear the bearing area of the glass;
3. c) the piercing tool is controlled to perform preprogrammed machining sequences, using the position of the glass reference point as the zero point of said sequences.

Thus, the zero point of the machining sequences is constituted for the numerically controlled drill by a reference point of the edge of the glass. It is easy to understand that the preliminary marking of such a reference point on one edge of the glass is totally independent of the profile of said glass, in particular of the shape of its outline which can adopt all the imaginable forms of fantasy that go well beyond beyond the geometric shapes usually used for spectacle lenses. We have therefore managed to abandon the registration with respect to a center of glass, which allows to proceed to machining glasses of any shape without having to memorize previously all the forms concerned. The only storage then relates to the types of machining sequences to be performed with the numerically controlled drill, depending on the connection mode between the glasses and the mount concerned.

Preferably, during step a), the right and left glasses of the glasses to be made are positioned side by side, each lens having a reference point which is brought in abutment against an associated fiducial point, after which each lens is immobilized. in its respective position, each reference needle being then retracted during step b) for the preprogrammed machining sequences respectively.

Advantageously then, the reference pins are part of the same retractable part on either side of which are brought the right and left lenses to perform symmetrically the holes in the nasal area or the temporal area of the two glasses . In particular, after completion of the preprogrammed machining sequences relating to the nasal or temporal area of the two glasses, the positions are substituted in a new step a) in order to then perform the sequences relating to the other zone.

It may further be provided that, during step a), the or each lens is moved and then immobilized on a slightly inclined plane laterally so that the piercing tool dock the relevant glass perpendicular to the relevant face of said lens.

It may also be provided that two inclined juxtaposed planes are provided, whose inclination is adjusted symmetrically for the right lens and the left lens.

Advantageously, during step b), retraction of the indexing needle (s) is performed automatically or manually, in a direction parallel to the vertical direction Z.

Preferably, finally, during step c), the machining sequences are taken from a memory into which a plurality of sequences, each comprising a plurality of notches and / or bores, whether through or not, arranged according to a predetermined pattern.

• une platine essentiellement horizontale portant une perceuse à commande numérique ayant un support d'outil en surplomb déplaçable en translation suivant trois directions de coordonnées X, Y, Z et dont l'outil de perçage est entraîné en rotation et déplaçable en translation suivant son axe qui reste essentiellement vertical ;
• un pointeau repère monté sur la platine, en étant déplaçable entre une position active d'appui de verre et une position escamotée dégagée du verre ; et
• un support de verre agencé pour maintenir un verre dans un plan essentiellement horizontal, ledit support reposant sur un plan solidaire de la platine précitée et étant immobilisable en position par rapport audit plan.

The invention also relates to a device for implementing a drilling method according to at least one of claims 1 to 8, said device being remarkable in that it comprises:

• a substantially horizontal plate carrying a numerically controlled drill having an overhanging tool support movable in translation along three coordinate directions X, Y, Z and whose drilling tool is rotated and displaceable in translation along its axis which remains essentially vertical;
• a reference pin mounted on the plate, being movable between an active position of support of glass and a retracted position released from the glass; and
• a glass support arranged to hold a glass in a substantially horizontal plane, said support resting on a plane integral with the aforementioned plate and being immobilizable in position with respect to said plane.

Preferably, the reference pin comprises a vertical pin fixed to the plate, and a slide movable on said pin between a high active position and a lowered retracted position, said slide having at least one lateral edge serving to support the edge of the glass concerned at a reference point of it.

Advantageously then, the slider of the reference pin has a lateral support edge on each side of the axis of the support pin, and two glass supports are provided in order to put in place the right and left glasses next to one another. the other. In particular, the lateral support edge provided on one or each side of the slider is a rib extending vertically.

It may further be provided that the upper position of the slide on its vertical column is ensured by mechanical or electromagnetic means, and that the downward movement of the slide on its vertical column is effected by mechanical, electrical or electromagnetic means. at the descent of the piercing tool.

According to a particular embodiment, the plate is surmounted by two support plates forming a dihedron, and the inclination upward or downwardly is symmetrically adjustable by an associated common control means. This makes it possible for the piercing tool to dock the glass perpendicularly to the relevant face of said glass.

Advantageously, the glass support comprises a disengageable magnetic locking block, immobilizable in any position on the plane or inclined plates surmounting the plate, the upper face of which is made of ferro-magnetic material, said block being surmounted by means of maintaining a glass in a substantially horizontal plane.

Preferably, finally, the glass support is secured to the plate so as to move in two orthogonal directions corresponding to the X, Y coordinate directions.

The following description and the accompanying drawings relate to a particular embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

• la figure 1 est une vue en perspective montrant un ensemble de perçage de verres optiques conforme à l'invention, mettant en oeuvre le procédé de perçage de l'invention ;
• la figure 2 est une vue partielle à échelle agrandie, illustrant en perspective un support de verre équipant le dispositif de la figure 1, ici du type à verrouillage magnétique débrayable, avec les moyens associés de guidage en X, Y ;
• la figure 3 est une vue de dessus schématique illustrant les étapes successives du procédé de perçage selon l'invention mis en oeuvre sur un verre unique ;
• la figure 4 est une vue de dessus schématique analogue à celle de la figure 3, illustrant une mise en oeuvre du procédé de l'invention sur le verre droit et le verre gauche des lunettes à réaliser ;
• les figures 5A et 5B sont deux vues en élévation illustrant la mise en place des verres sur des plans légèrement inclinés latéralement, afin que l'outil de perçage accoste le verre perpendiculairement à la face respectivement convexe ou concave concernée.

Reference will be made to the figures where:

• the figure 1 is a perspective view showing an optical glass piercing assembly according to the invention, implementing the piercing method of the invention;
• the figure 2 is a partial view on an enlarged scale, illustrating in perspective a glass support equipping the device of the figure 1 here of the releasable magnetic locking type, with the associated X, Y guide means;
• the figure 3 is a schematic top view illustrating the successive steps of the drilling method according to the invention implemented on a single glass;
• the figure 4 is a schematic top view similar to that of the figure 3 , illustrating a process of the invention on the right lens and the left lens glasses to achieve;
• the Figures 5A and 5B are two elevational views illustrating the placement of the glasses on slightly laterally inclined planes, so that the piercing tool docking the glass perpendicular to the respectively convex or concave face concerned.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

We distinguish on the figure 1 an optical glass piercing assembly marked 10. The assembly 10 comprises a substantially horizontal plate 11, carrying a numerically controlled drill 12. The digital drill 12 here comprises subassemblies 13.1, 13.2, 13.3, the last including an engine electric drive not visible here, motor whose output shaft is coupled to a mandrel 14 for fixing a drilling tool 15 such as a milling cutter. The drilling tool is rotated about its axis 16 by the associated motorized means. In this case, the numerically controlled drill 12 comprises a lower block 13.1 which is mounted on the plate 11 to be able to move in two directions of X, Y coordinates, which block is surmounted by a tool support 13.3 mounted on a mobile vertical column 13.2. The tool support 13.3 is thus controllably movable in a substantially vertical Z coordinate direction, in addition to the X, Y coordinate directions due to its mounting on the block 13.1.

Thus, the piercing tool 15 is movable both in the X, Y directions of a horizontal plane, and in the direction of its axis in the Z coordinate direction, as shown by the double arrow 100. In practice , the piercing tool 15 will be a milling cutter of small diameter, for example of the order of 1 mm, preferably to a drill, in order to be able to make holes of larger diameter by milling without changing the tool, and more generally to achieve any form of drilling or milling, open or not.

The movement control of the drilling tool 15 can be carried out directly on the apparatus by means of setting buttons and associated switches formed on the front face of the plate 11, these buttons and switches being referenced 17.1, 17.2, 17.3, 17.4, 17.5 and 17.6. We also illustrated on the figure 1 a PC computer 18 associated with a keyboard 19, the assembly being connected by a cable 18.1 to the digital drill 12. This computer assembly is therefore capable of sending displacement instructions for making a predetermined trajectory by the tool 15. As will be seen below, the computer assembly 18 not only makes it possible to monitor the smooth running of the preprogrammed machining sequences, but also to have in memory a certain number of standard sequences in accordance with FIG. function of the holes and / or notches to be made in the lens or glasses concerned.

The drilling assembly 10 also comprises a horizontal plate 20 mounted on the plate 11, said plate forming a bearing plane and being in this case constituted by a unit plate of ferro-magnetic material. There is also provided a glass holder 50 arranged to hold a glass V in a substantially horizontal plane, said support resting on the plate 20 being immobilisable in position relative to said plate.

We also distinguish on the figure 1 certain equipment associated with the glass support 50, which is here produced in the form of a block 51 with detachable magnetic locking, immobilizable in any position on the plate 20. There is also a distinction between figure 1 a button 53 for controlling the immobilization in position of the support block 51, and a holding means 55 for positioning the glass to be machined. The arrangement of the support block 51 will be better understood by referring to the description part given below with reference to the figure 2 .

We also distinguish the presence, on the plate 20, of two C-shaped slides 25 facing each other and each including a rack 26. A transverse bar 27 whose ends carry gables (not visible on the figure 1 ) meshing each with a respective rack, serves to ensure the X, Y positioning of the support block 51 through an overlapping profile 52 passing without play on the crossbar 27. The X, Y displacements of the support block 51 are here schematized by double arrows respectively 102 and 101.

The figure 1 also makes it possible to distinguish another means whose function is essential in the context of the present invention. It is indeed a reference pin consisting generally of a set 30, and whose position in the X, Y plane is known from the numerically controlled drill 12. The reference pin 30 here comprises a small column vertical 31 fixed to the plate 11 (in this case directly on the plate 20), and a slide 32 movable vertically on said small column, said slide having at least one lateral edge 33 constituted by a tapered rib extending vertically. In this case, there is provided a lateral edge 33 on each side of the slider 32, this rib is preferably rigid plastic, such as nylon or the like, to be both accurate and not to risk splinters or more generally to damage the edge of the glass which is brought into abutment against said rib, according to the procedure which will be described hereinafter in more detail.

The figure 2 makes it possible to better distinguish the glass support 50 which is arranged to hold a glass V in a substantially horizontal plane, as well as the needle-locating assembly 30 (here in the upper glass support position).

The set needle pointer 30 thus comprises a column of vertical axis 31, here of rectangular section, on which can move a slide 32 bearing laterally projecting on each side of the axis of the column, a vertical rib tapered 33. This reference needle is mounted on the column 31 being movable between a high position (shown in solid lines) which corresponds to an active position of support of glass, as shown in FIG. figure 2 , and a lowered position retracted (as schematized by a portion of rib illustrated in dashed line on the figure 2 ) which is clear of the glass.

The holding in high position of the slide 32 on its vertical column can be provided by mechanical or electromagnetic means, which have not been shown here. This may be for example an erasable snap ball, or a magnet, or any other equivalent means. The passage from the high position to the lower position of the slider 32 may also be performed by mechanical, electrical or electromagnetic means, related to the descent of the drilling tool, or alternatively manually by acting directly on the slider to drive it on its small column. A simple way to achieve automatic control of the downward movement of the slider 32 is to provide a vertical rod (not shown here) fixed on the tool support 13.3 and which bears on the slider 32 at the lowering of the slider. drilling tool, so that the pointer mark is automatically retracted when the piercing tool arrives in a Work zone. Any system based on a cable or electromagnet may alternatively be used to control the automatic lowering of the slide downwards.

It should be noted that the reference pin illustrated here has two lateral bearing edges 33, on either side of the axis of the column, which allows to bring two glasses to be machined, from both sides of the column. other of the pointer mark.

The figure 2 further illustrates in more detail the glass holder 50, which is arranged to hold a glass V in a substantially horizontal plane. The glass support 50 is thus made in the form of a disengageable magnetic locking block 51, which is immobilizable in any position on the plate 20 whose upper face is made of ferro-magnetic material. A control knob 53 can rotate, as shown schematically by the double arrow 105, between two positions respectively corresponding to the immobilization in position of the block 51 on the upper face of the plate 20, or the release of the magnetic lock to allow free sliding of the block 51 on the upper face of the plate 20. It is also possible to distinguish figure 2 the overlapping profile 52 which is rigidly secured to the block 51, and which passes without play and with a minimum of friction, on the transverse bar 27 which is distinguished by an end pinion 28 meshing with the associated rack 26 disposed in the profile. C shape 25. The displacement in a direction parallel to that of the racks 25 corresponds to a displacement in Y schematized by the double arrow 101, and the transverse displacement, along the axis of the bar 27, corresponds to a displacement in X schematized by the double arrow 102. The support 50 is thus secured to the plate 20 to move in two orthogonal directions 101, 102 forming a coordinate system in X, Y.

The block 51 with magnetic locking is also surmounted by a means 55 for holding a glass V in a substantially horizontal plane. This holding means 55 may in practice be made in different ways, and there is illustrated here a bracket 54 rigidly secured to the block 51, said bracket supporting a movable assembly forming clamp. This moving assembly comprises an operating element 60 constituted by a wheel 61 rotatably coupled to a rod 62 whose lower portion 63 is threaded, so that the rotation in one direction or the other, as shown schematically by the double arrow 106 , makes it possible to raise or lower a terminal holding pad 59. The glass V rests on a fixed part constituted by a support 56 secured to the block 51, which support is surmounted here by a flexible assembly 57 ending in a ring washer 58. As a variant of the flexible means 58, 59 used for tightening the glass, it is possible to use the superimposed support ending in a clamping shoe mounted on a ball joint, thus making it possible to adapt naturally to the various curvatures of the internal and / or external faces. glasses to be clamped, each pad being preferably equipped with a ring washer ensuring contact with the glass without the risk of scratching the surface thereof. Moreover, one or other of the parts that comes into contact with the glass may include a suction cup accessory (not shown here) for receiving, for example by interlocking, different models of suction cups used on glass grinders optical, and also a simple piece having an O-ring to tighten glasses without suction cups.

The structural components of the device having been described in detail with reference to the figures 1 and 2 , we will now be able to describe the method of drilling optical glasses according to the invention with reference to the figures 3 and 4 which are more schematic.

On the figure 3 firstly, a first step denoted a1) is distinguished, in the course of which an optical glass V is placed on an edge of which a particular point PR has been marked, which is a reference point for the sequences of machining which will have to be carried out later on the glass. The glass V is of course fixed on its magnetic type support not shown here. The support is movable in sliding support on the plate 20 in X, Y, which allows to gradually move the glass V to bring the reference point PR exactly at the tip of the needle pin rib 33, as shown in a2). Thus, in this step, the glass V is positioned by moving it in a plane substantially perpendicular to the axis 16 of the piercing tool, with respect to the reference pin 33 whose position in said plane is known to the control drill. 12, up to bring the reference point PR, previously marked at the edge of the glass V, against the reference needle 30, 33, after which said glass is immobilized in this position. The immobilization is carried out very simply, by turning the control knob 53 of the magnetic support 50.

In the next step b), the piercing tool 15 (not shown) is then brought closer to the glass V still immobilized, and the needle pointer 30, 33 is retracted to clear the bearing zone of the glass as is schematized by the dotted line representation of said reference needle. The piercing tool 15 can then perform any desired trajectory previously established with respect to the glass whose position is known by the reference point PR.

According to step c), the piercing tool 15 is controlled to perform preprogrammed machining sequences, using the position of the reference point PR of glass V as the zero point of said sequences.

• motif M1 : un perçage traversant P1 et une encoche débouchante E1 ;
• motif M2 : deux perçages traversants P2.1, P2.2 qui sont sensiblement superposés ;
• motif M3 : deux perçages traversants P3.1, P3.2 sensiblement alignés horizontalement ;
• motif M4 : un perçage traversant allongé L4 dans une direction sensiblement verticale ;
• motif M5 : un perçage traversant P5 et une encoche non-débouchante E5 ;
• motif M6 : un usinage surfacique non débouchant P6 conformément à un motif à finalité technique et/ou esthétique.

The machining sequences are preferably taken from a memory into which a plurality of sequences, each comprising a plurality of notches and / or bores, whether through or not, arranged in a predetermined pattern, are entered. These sequences will concern in species the ZN nasal area of the glass concerned V. There is illustrated here different patterns M1 to M6 corresponding to machining commonly encountered for this type of frame. These different reasons are schematized on the figure 3 , where we distinguish:

• M1 pattern: a through hole P1 and a notch E1;
• M2 pattern: two through holes P2.1, P2.2 which are substantially superimposed;
• pattern M3: two through holes P3.1, P3.2 substantially aligned horizontally;
• pattern M4: an elongated through bore L4 in a substantially vertical direction;
• pattern M5: a through hole P5 and a non-through slot E5;
• pattern M6: a non-emerging surface machining P6 in accordance with a pattern with a technical and / or aesthetic purpose.

In all cases, the piercing tool 15 is controlled to perform preprogrammed machining sequences, using the position of the reference point PR of the glass V as the zero point of said sequences.

Once the holes in the nasal area ZN have been made, the same sequence of operations can be used to perform the holes in the temporal zone ZT of the same lens. This has been schematized by step a '), during which the support of the glass V has been moved again in the plane X, Y to bring another reference point PR' previously marked on the opposite edge of the V glass bears against the needle mark 30, 33, after which the glass is again immobilized in this position. Steps b) of approaching the tool for drilling and retraction of the reference needle, then c) control machining sequences and / or preprogrammed notches, then allow to achieve the desired holes for the temporal zone ZT.

We will now illustrate an advantageous variant of the method described above, which allows to work directly on the right lens and the left lens glasses to achieve, with reference to the figure 4 .

As schematized in a1), the right glass VD and the left glass VG, fixed on their respective magnetic support, have been previously placed in abutment on the plate 20. The reference needle 30 comprises in this case absolutely two protruding protruding ribs 33, on both sides the axis of the fixed column 31.

Each support will then be moved to bring the reference point PR of each glass VD or VG against a lateral support edge 33, as shown in a2). Then, we find similar steps to those previously described, with b) the retraction of the double needle reference 33 when approaching the drilling tool 15, and c) the control of the drilling tool for performing preprogrammed machining sequences on each lens, using the respective position of the reference point PR as the zero point of said sequences.

It should be noted that the guiding means of the glass supports used here make it possible to guarantee perfect alignment of the VD and VG glasses in the X direction, so that, in practice, it will be sufficient to mark a PR mark on only one of the two glasses, after which the support of the other glass is simply moved in the X direction until the free edge of the glass concerned comes into contact with the other lateral support edge 33.

This is made possible by the fact that the two glasses with their respective grinding cups are placed which is perfectly centered on the associated glass, so that the two glasses are wedged rigorously symmetrically with respect to a median vertical plane, in the same axis, and at the same height.

Thus, as illustrated in c), the holes and / or notches desired on the right and left glasses VD and VG, in this case here a piercing P1 and a notch E1 opening.

To carry out the machining of the temporal zones of each of the glasses, it is possible to take advantage of the positioning means described above by contenting itself with a simple substitution of the two glass supports, in order to directly bring the free edges of the temporal zones into abutment against the Lateral support edges 33. This is illustrated in step a ') where it is found that the right and left lenses have been substituted.

After this step a '), the process resumes as before, with retraction of the double reference needle, and controls preprogrammed machining sequences for each of the glasses, in the temporal zone thereof.

The procedure just described is perfectly suitable for the machining of corrective or non-corrective lenses, of all shapes of contours, and of any thickness or material.

In some cases, particularly when the curvature of the glasses is large, it may be advantageous to seek an inclined orientation of the glass to be machined, so that the vertical axis drilling tool attacks the relevant surface of the glass substantially perpendicularly. in the tangent plane.

The device of the invention has been arranged for this purpose, and we will refer for this purpose to Figures 5A and 5B .

In these figures, the horizontal plate 20 of the plate is recognized, and the tool support 13.3 supporting the drilling tool 15. There are also two glass supports 50 whose structure remains unchanged. The main modification lies in the presence of one or two (here two) support plates 41 whose inclination is adjustable. Indeed, by laterally inclining the bearing surface on which the glass support 50 rests, it is possible to modify the inclination of the glass fixed on said support, so that the face to be machined locally has a substantially horizontal tangent plane.

In this case, there are provided two support plates 41, articulated at a central pivot 42 extending in the Y direction, and thus forming a dihedron. The inclination of the two support plates 41 upwards or downwards is symmetrically adjustable by an associated common control means 45, here constituted by an assembly with superposed washers 46 and an operating wheel 47 allowing, by rotation of the latter around a vertical axis, to change the inclination of the support plates 41, while maintaining symmetry with respect to a median vertical plane.

On the Figure 5A , the central portions of the support plates 41 are raised, in order to attack the convex face of the glasses by the piercing tool 15. Conversely, the Figure 5B , the central portions of the support plates 41 have been lowered, with a view to a perpendicular attack of the concave face of the two glasses by the piercing tool 15.

It should be noted that the displacement of the magnetic supports 50 on the inclined plates 41 is in no way influenced by the rack guide means previously described, thanks to the guide system given by the bracket 52 associated with each block 51 of the support of glass 50.

Thanks to the symmetry, one is sure to have an excellent attack for the convex or concave faces of each of the two right and left lenses.

Thus, a method and a device for drilling spectacle lenses using a small numerical control drill, which is a valuable equipment for the optician, intermediate between the manual drills and the digital drills of the large ones, has been achieved. workshops.

Of course, the operator can follow the smooth running of the machining sequences on the screen of his computer 18. It will be interesting for this reason to provide that the screen systematically presents in icon a representation of the selected machining pattern, this to avoid any error in the machining of glasses. In all cases, only the machining patterns are to be memorized, it being understood once again that the drilling method according to the invention is in no way dependent on the shape of the outline of the glass.

The invention is not limited to the embodiment that has just been described, but on the contrary covers any variant incorporating the characteristics of independent claim 1 or of independent claim 9.

Claims (17)

1. A method of drilling holes in lenses for making "rimless and pierced-lens" spectacles by means of a numerically-controlled drill (12) having a tool support (13.3) that is mounted to move in translation in three co-ordinate directions X, Y, Z, the associated drill tool (15) being drivable in rotation about and movable in translation along its axis (16) which is parallel to one (Z) of said directions, said method being characterized in that it comprises the following successive steps:

   a) positioning a lens (V) by moving it in a plane substantially perpendicular to the axis (16) of the drill tool, relative to a reference pointer (30, 33) of position in said plane that is known to the numerically-controlled drill (12), until a pre-marked reference point (PR) on an edge of the lens (V) is brought into abutment against the reference pointer (30, 33), whereupon said lens is held stationary in that position;

   b) then bringing the drill tool (15) towards the lens (V) which continues to be held stationary, and retracting the reference pointer (30, 33) in order to leave clear the abutment zone of the lens; and

   c) controlling the drill tool (15) so as to perform the pre-programmed machining sequences, by using the position of the reference point (PR) of the lens (V) as a zero point for said sequences.
2. A method according to claim 1, characterized in that, during the step a), the right and the left lenses (VD, VG) of the spectacles to be made are placed side-by-side, each lens having a reference point (PR) which is brought into abutment against an associated reference pointer (30, 33), whereupon each lens (VD, VG) is held stationary in its respective position, each reference pointer (30, 33) then being retracted during step b) for the respective pre-programmed sequences.
3. A method according to claim 2, characterized in that the reference pointers (30, 33) are part of a common retractable piece (32) on either side of which the right and the left lenses (VD, VG) are brought to enable the holes in the nose zones (ZN) or in the temple zones (ZT) of both lenses to be formed symmetrically.
4. A method according to claim 3, characterized in that, after completion of the pre-programmed machining sequences on the nose zones (ZN) or on the temple zones (ZT) of both lenses (VD, VG), the positions are swapped over in another step a) in order then to perform the sequences on the other zones.
5. A method according to any one of claims 1 to 4, characterized in that, during step a), the or each lens is moved and then held stationary on a surface (41) that is laterally tilted with a small angle of inclination so that the drill tool (15) meets the lens in question perpendicularly to the face in question of said lens.
6. A method according to any one of claims 2 to 4, and claim 5, characterized in that two juxtaposed sloping surfaces (41) are provided, of inclinations that are adjusted symmetrically for the right lens (VD) and for the left lens (VG).
7. A method according to any one of claims 1 to 6, characterized in that, during step b), the reference pointer(s) (30, 33) is/are retracted automatically or manually, in a direction parallel to the vertical direction (Z).
8. A method according to any one of claims 1 to 7, characterized in that, during step c), the machining sequences are taken from a memory in which a plurality of sequences have been input, each of which includes a plurality of through or non-through holes and/or notches, arranged in a predetermined pattern (M1 to M6).
9. Apparatus for implementing the drilling method according to any one of claims 1 to 6, said apparatus being characterized in that it comprises:

   a substantially horizontal bed (11) carrying a numerically-controlled drill (12) having an overlying tool support (13.3) that is movable in translation in three co-ordinate directions X, Y, Z and having a drill tool (15) that is drivable in rotation about and is movable in translation along its own axis (16) which remains substantially vertical;

   a reference pointer (30, 33) mounted on the bed (11) to be movable between an active position in which it bears against a lens and a retracted position in which it leaves the lens clear; and

   a lens support (50) arranged to hold the lens (V) in a substantially horizontal plane, said support resting on a surface (20, 41) that is secured to or integral with the above-mentioned bed (11) while the position of said support can be held stationary relative to said surface.
10. Apparatus according to claim 9, characterized in that the reference pointer (30) comprises a vertical column (31) fixed to the bed (11) and a slide (32) mounted to move on said column between an active high position and a retracted low position, said slide having at least one side edge (33) serving as an abutment for the edge of the lens in question at a reference point (PR) thereon.
11. Apparatus according to claim 10, characterized in that the slide (32) of the reference pointer (30) has an abutment side edge (33) on either said of the axis of the support column (31), and two lens supports (50) are provided in order to put in place the right and left lenses (VD, VG), one next to the other.
12. Apparatus according to claim 10 or claim 11, characterized in that the abutment side edge (33) provided on one side or on each side of the slide (32) is a vertically extending rib.
13. Apparatus according to any one of claims 10 to 12, characterized in that the slide (32) is held in the high position on the vertical column (31) by mechanical or electromagnetic means.
14. Apparatus according to any one of claims 10 to 13, characterized in that the slide (32) is caused to move downwards over its vertical column (31) by mechanical, electrical, or electromagnetic means associated with the drill tool (15) moving downwards.
15. Apparatus according to any one of claims 9 to 14, characterized in that the bed (11) underlies two support plates (41) forming a V-shape, and whose upward or downward inclination is adjustable symmetrically by associated common adjustment means (45).
16. Apparatus according to any one of claims 9 to 15, characterized in that the lens support (50) comprises a block (51) having declutchable magnetic locking, that can be held stationary in any position on the surface (20) or on the inclined plates (41) overlying the bed (11), the top face of said block being made of a ferromagnetic material, and said block underlying means (55) for holding a lens (V) in a substantially horizontal plane.
17. Apparatus according to any one of claims 9 to 16, characterized in that the lens support (50) is secured to the bed (11) so as to move in two orthogonal directions corresponding to the co-ordinate directions X and Y.

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