FR2878974A1 - Organ for handling and palping an ophthalmic lens of goggles and device for automatically preparing the mounting of ophthalmic lenses comprising such a body - Google PatentsOrgan for handling and palping an ophthalmic lens of goggles and device for automatically preparing the mounting of ophthalmic lenses comprising such a body Download PDF
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- FR2878974A1 FR2878974A1 FR0412850A FR0412850A FR2878974A1 FR 2878974 A1 FR2878974 A1 FR 2878974A1 FR 0412850 A FR0412850 A FR 0412850A FR 0412850 A FR0412850 A FR 0412850A FR 2878974 A1 FR2878974 A1 FR 2878974A1
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B9/00—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor
- B24B9/02—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground
- B24B9/06—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of non-metallic inorganic material, e.g. stone, ceramics, porcelain
- B24B9/08—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of non-metallic inorganic material, e.g. stone, ceramics, porcelain of glass
- B24B9/14—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of non-metallic inorganic material, e.g. stone, ceramics, porcelain of glass of optical work, e.g. lenses, prisms
- B24B9/146—Accessories, e.g. lens mounting devices
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B13/00—Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor
- B24B13/0031—Machines having several working posts; Feeding and manipulating devices
TECHNICAL FIELD TO WHICH THE INVENTION REFERS
The present invention generally relates to the mounting of ophthalmic lenses of a pair of corrective eyeglasses on a frame and more particularly relates to a manipulating and probing member of an ophthalmic lens and an automatic lens preparation device. a pair of glasses for mounting on the frame chosen by the wearer.
The technical part of the optician's profession is to mount a pair of ophthalmic lenses in or on the frame selected by the wearer, so that each lens is properly positioned facing the corresponding eye of the wearer to best exercise the optical function for which it was designed. To do this, it is necessary to perform a number of operations.
After the choice of the frame, the optician must first locate the position of the pupil of each eye in the frame of the frame. It thus determines, principally, two parameters related to the morphology of the wearer, namely the inter-pupillary distance as well as the height of the pupil relative to the frame.
With regard to the mount itself, it is necessary to identify its shape, which is usually done using a template or a device specifically designed to read the inner contour of the "circle" (c '). that is to say the frame of the lens) of the frame, or of an electronic file pre-recorded or supplied by the manufacturer.
From these geometrical input data, it is necessary to proceed with the trimming of each lens. The trimming of a lens for mounting in or on the frame chosen by the future carrier is to change the contour of the lens to adapt to the frame and / or the desired lens shape. The trimming includes the edging for shaping the periphery of the lens and, depending on whether the frame is of circle type or without circles with pinch point through a fixing hole in the lens, beveling and / or the proper drilling of the lens. The edging, (or trimming itself) consists in eliminating the superfluous peripheral part of the ophthalmic lens concerned, to bring back the contour, which is most often initially circular, to that whichever of the circle or surround of the spectacle frame concerned or simply to the desired aesthetic shape when the frame is of the type without circles. This edging operation is usually followed by a chamfering operation which consists of cutting or chamfering the two sharp edges of the edge of the overflow lens. When the assembly is of the circle type, this chamfering is accompanied by a beveling consisting in ensuring the formation of a rib usually called bevel, usually triangular cross section whose top is blunt or broken by a counterbore, on the edge of the ophthalmic lens. This bevel is intended to be engaged in a corresponding groove, commonly called bezel, formed in the circle or surround of the eyeglass frame in which the lens is to be mounted. When the mount is of the type without a circle, the trimming of the lens and, possibly, the reduction of the sharp edges (chamfering) are followed by the appropriate drilling of the lenses to allow the fixation of the branches and the nasal bridge of the mount without circle. Finally, when the assembly is of the Nylon-wire strapping type, the chamfering is accompanied by a groove consisting in providing a groove in the edge of the lens, this groove being intended to receive the nylon wire of the frame intended to press the lens against the rigid part of the frame.
Most often, these operations of edging, chamfering and beveling are successively conducted on the same grinding machine, called grinder, equipped with a train of appropriate wheels. The drilling can be performed on the grinder which is then equipped with the corresponding tooling or on a separate drilling machine.
The optician must also carry out a certain number of measuring and / or marking operations on the lens itself, before trimming, to identify some of its characteristics such as for example the optical center in the case of a unifocal lens or the cross mounting in the case of a progressive lens, or the direction of the axis of progression and the position of the centering point for a progressive lens. In practice, the optician defers certain characteristic points with a striking point on the ophthalmic lens itself. These marks are used to fix on the lens an adapter or acorn centering and drive to properly position the ophthalmic lens in the grinding machine to give it the desired contour, corresponding to the shape of the frame chosen. This glans is most often stuck temporarily on the lens with a double-sided adhesive. This operation is usually called the centering of the lens, or by blocking extension of the lens since the glans can then block, that is to say immobilize, the lens on the means of its trimming in a known geometric configuration thanks to this acorn.
After placing the centering glue, the lens thus equipped is then placed in the clipping machine where it is given the shape corresponding to that of the chosen frame. The centering glide makes it possible to define and physically materialize on the lens a geometric reference frame in which the points and the characteristic directions of the lens, necessary for the coherence of this lens with the position of the pupil, and the values are identified. of clipping so that these points and characteristic directions are properly positioned in the frame.
In some cases, it may happen that the trimming of the lens does not result at first blow to a good mount in the mount. The operator must then resume machining. To do this, it puts the lens in the machine and blocks it with the same tassel, which allows to recover the initial clipping repository.
However, the use of a glued glue is a disadvantage in that it must be removed after mounting the lens. In addition, the lens is secured to the glans by gluing which requires to particularly intensively clean the surface of the lens after treatment, resulting in a risk of scratching. Finally, these operations of laying and removal of the glans being relatively complex and delicate, they require a skilled and careful workforce and are in practice time-consuming and therefore expensive; and for the same reasons, it is difficult to automate them.
On the other hand, during the placement of the glans and more specifically the contacting of the latter with the front surface of the lens, it is approached with a degree of mobility reduced to a simple translation, so that the Acorn accost the lens at a slightly oblique angle of incidence, so that the contact of the glans with the lens causes a relative tilting. As a result of this tilting, an error in positioning the glans on the lens. This error would be renewed and therefore amplified if one had, after the glans was removed, perform a recovery of the clipping of the lens with repositioning of the glans. The repeated error of positioning of the glans would then create an accumulation or error drift. Because of this positioning drift, a recovery of the lens without glued accessory has so far been considered.
Depending on the organization and the equipment available to the optician, the distribution of the operations mentioned above can be done on two or three separate workstations. Each lens being processed must be transferred from one workstation to another. Inaccuracies, errors or incidents are therefore possible due to the multiplication of manipulations. Moreover, if these operations are carried out within the framework of an industrial organization, this results in a considerable loss of time and a high cost of production. In addition, the risk of degradation of the ophthalmic lens increases with the number of manipulations, which greatly increases delivery times and further increases costs.
In document FR2825308 or its equivalent EP1392472, it has been proposed to optimize the process described above by partially automating the measurement and positioning phases of the ophthalmic lens, which makes it possible to determine the optical characteristics of the lens and to control the transport phase of this lens to the clipping station and the clipping phase itself.
The device thus proposed comprises means for measuring the identification characteristics of said lens and means for trimming said lens making it possible to reduce the contour of the lens to the desired shape. Conventionally, these clipping means are constituted by a grinder which has a set of grinding wheels and means for locking and driving in rotation of the lens constituted by two coaxial rotary shafts mounted axially movable to tighten the lens along the axis of that like a plier. To allow the approximation or spacing of the lens relative to the grinding wheels during machining, the clamping and driving shafts are carried by a transversely movable rocker (in pivoting or translation).
Partial automation of the lens preparation process is obtained by means of a sliding carriage and transfer carriage arranged to transfer the ophthalmic lens according to two transfers between three positions, with a transfer between a measurement position, in which the lens Ophthalmic is presented next to the measuring means, and an intermediate position distinct from the measuring position, then a transfer between said intermediate position and a separate cutting position of the intermediate and measuring positions.
But in this device, the transfer of the lens from its intermediate position to the clipping means is provided directly by the clamping shafts and rotating the clipping means, exploiting the transverse mobility of the rocker carrying the shafts. the grinder. This way of transferring the lens to the clipping means offers the dual advantage of saving resources and keeping the reference frame of the lens defined on the measuring means. But it imposes in return penalizing limitations.
This results in particular, in use, a lack of flexibility in the seizure of the lens by the rocker and, therefore, difficulties and inaccuracies in locking the lens. However, the locking operation of the lens is particularly critical for the overall accuracy of the trimming, especially when it is necessary to perform a recovery.
The end caps fitted to the ends of the shafts of the grinder are fixed permanently on the shafts and are therefore used to block all the lenses, whatever the dimensions and coatings of these lenses. We are therefore forced to choose for these tips medium properties that are not suitable for some lenses. This may result in lens slippage during trimming, which distorts the centering and focusing of the lens in the frame, degrading its optical performance.
The loading before optical measurement on the measuring device and the unloading after trimming of the (lens by the operator on the carriage is done without protection, at the measurement or intermediate positions, so that the loading and unloading of the lenses on the truck is firstly left to the initiative and the benevolence of the operator (who must distinguish whether the processing of the lens is outstanding or completed) and assumes direct access to the measuring device, this which makes the latter vulnerable to external aggression of all kinds and in particular to fouling, and secondly to the lens in the intermediate position in which it is nevertheless essential to preserve the lens from any untimely movement. loading position and the intermediate position can not be considered in the state can be considered without increasing the overall size of the device and a deterioration of performance and / or cost drift.
It should also be taken into consideration that the scale of the grinder and in particular the end tips of the shafts used for blocking the lens are, because of the treatment of the lenses and the removal of material with the possible lubrication that accompanies it, systematically soiled by a kind of mud. As this rocker also ensures the transfer of the lens from the carriage to the trimming means and cooperates for this transfer with the transfer carriage, this results in a gradual fouling of the transfer carriage which conveys the lens in measuring position. It is understood that this fouling is very disadvantageous, insofar as it may disturb, or at least, deteriorate the optical performance of the measuring means.
Finally, except to complicate the kinematics of the organs of the grinder (with the inaccuracy and / or cost increase that would result), there are several functional limitations of importance.
As regards the gripping and the third transfer of the lens, the latter can only be grasped by the scale of the grinder with a single degree of freedom of positioning in the plane of the lens (in addition to the rotation of the lens. the locking shaft of the lens about its axis which makes it possible to adjust the axis of the lens, that is to say orientation of the lens with respect to the locking shaft about its axis), this can penalize the accuracy of the blocking and, therefore, the overall clipping. This inaccuracy of blocking is particularly penalizing in case of recovery of a poorly cut lens.
On the other hand, with regard to the probing of the lens, it can be palpated on the grinder only after the locking of the lens and with limited degrees of mobility of the probe and the grinder. However, it is often necessary to perform several probes of the lens. If all the probes are performed on the grinder, the lenses can be processed only sequentially, without it being possible to perform a parallel probing of a trimming since the probing occupies the trimming means and makes them unavailable for their main function of clipping. In addition, a probe prior to the blocking could provide geometrical information useful to the precision of the blocking of the lens and the studies of the plaintiff led him to consider that the defect of such a preliminary probing can penalize the accuracy and reliability probing and thus blocking and, therefore, global trimming. This inaccuracy of blocking proves particularly penalizing in case of recovery of a poorly cut-out lens.
OBJECT OF THE INVENTION An object of the present invention is to provide an alternative solution that improves the functions of gripping and probing. Another object of the present invention is to provide an alternative solution of probing and lens gripping that allows to overcome the constraints and inaccuracies imposed by the direct grip of the lens by the rocker of the grinder on the first transfer means . Other objects of the invention are, in particular, to preserve the integrity and the cleanliness of the means of reception, first transfer and second transfer and / or to improve the fluidity of the flow of treatment of the lenses and / or providing the third transfer means with a more accurate and versatile manner of grasping the lens to allow precise lens lock engagement and recovery.
For this purpose, the invention proposes a device for manipulating and probing an ophthalmic lens, comprising a wrist that is movable in a fixed frame of reference according to at least one degree of controlled mobility and which is provided with both means gripping and sensing means of an ophthalmic lens.
Thus, with a single member and therefore with a small footprint, flexible and versatile gripping and sensing means, independent of the clipping means and able to perform both: a probing of the lens out of the means third transfer, so as to leave free these for their specific function of clipping; - A gripping according to a kinematic blocking accurate and adapted case by case to the lens in preparation.
According to an advantageous characteristic of the invention, the wrist has at least three degrees of mobility controlled.
These degrees of mobility of the organ allow it to approach the lens in any direction of docking of the lens for gripping or probing.
In a preferred embodiment, the wrist has only five degrees of controlled mobility. The five degrees of mobility of the wrist include a horizontal translation, a vertical translation and three rotations. The wrist is hingedly mounted on a bearing limb for pivoting relative thereto along two distinct axes, said stub being movably mounted in vertical translation on a vertical beam which is rotatably mounted around the vertical on a carriage which is itself mounted to slide on a fixed horizontal beam.
In an advantageous embodiment, the gripping means comprise an upper jaw and a lower jaw mounted on the wrist movable relative to each other to form a clamp and the probing means comprise two movable wrist-mounted legs. relative to each other to form a clamp or comparator.
Advantageously then, each of the branches of the probing means has a free angled end pointing to that of the other branch.
In a first embodiment, the jaws of the gripping means are arranged and movable relative to one another in a first plane and the branches of the probing means are arranged and movable relative to one another. another in a second plan distinct from the first. It may be advantageous to provide that said first and second planes are not parallel to each other.
In a second embodiment, the jaws of the gripping means are arranged and movable relative to each other in a plane and the branches of the probing means are arranged and movable relative to each other in this same plane.
The jaws of the gripping means and the branches of the probing means are mounted on the wrist so as to be relatively mobile in translation in a common direction. The jaw of the gripping means which is intended to cooperate with the convex face of the lens is fixedly mounted on the wrist.
Advantageously, each of the two jaws of the gripping means is provided at its free end with temporary fixing means (for example, clipping and / or magnetic means) of a tightening nose of a lens, the two noses being , after their temporary fixation on the jaws, arranged to sandwich the lens. The temporary fixation of the nose is automatically realized from a nose store comprising several nose sizes of different sizes adapted to the lens. The jaws are controlled by an associated control and control electronics to exert a predetermined clamping force on the lens by sandwiching this lens between two noses.
The jaws are controlled by the control electronics and control to measure or validate a spacing of the two nose to recognize and discriminate several pairs of nose of different sizes.
The invention also relates to a device for automatic preparation for mounting ophthalmic lenses, comprising: - means for automatically measuring the locating characteristics of an ophthalmic lens, - means for trimming an ophthalmic lens including means for axial clamping of this lens, and - transfer means, arranged to transfer an ophthalmic lens according to at least two transfers between at least three positions, with a second transfer between a measurement position, in which the ophthalmic lens is presented opposite the measuring means (5), and an intermediate position distinct from the measuring position, and a third transfer between said intermediate position and a separate cutting position of the intermediate and measuring positions, in which the lens is presented for its trimming by the clipping means, device in which the transfer means are decomposed into: on the one hand, second transfer means arranged to carry out the second transfer of the ophthalmic lens, and on the other hand, third transfer means loaded with the third transfer of the ophthalmic lens and constituted by a manipulation member and 25 probing as defined above.
DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT
The following description with reference to the accompanying drawings of an embodiment, given by way of non-limiting example, will make it clear what the invention consists of and how it can be achieved.
In the accompanying drawings: - Figure 1 is a schematic top view of the automatic preparation device for mounting ophthalmic lenses according to the present invention; - Figure 2 is an overall perspective view of the outside of the automatic preparation device provided with a cowling; - Figure 3 is a view similar to Figure 2, an access door of the cowling having been opened to allow the loading and unloading lenses to be prepared respectively on and off means of reception and first and second transfers; FIG. 4 is a perspective view of the interior of the automatic preparation device; - Figure 5 is a perspective view of the carousel and seats forming the reception means and first and second transfer; FIG. 6 is a perspective view of a part of the automatic preparation device, on which the carousel of the reception and first and second transfer means has been removed, revealing the tongs of the means of reception and of first and second transfers, with their actuating mechanism; FIG. 6A is an enlarged perspective perspective view of the one finger of the forceps of FIG. 6; - Figures 7 and 8 are respectively perspective views and from above the opening mechanism of the clamps of Figure 6; FIG. 9 is a view similar to FIG. 3, two first ophthalmic lenses L1, L2 (or first job) of a first pair of spectacles having been loaded onto the reception means and first and second transfers in two locations. loading separated from each other by two unloading locations; - Figure 10 is a perspective view of the preparation device in the configuration of Figure 9, the cowling having been removed; FIG. 11 is a perspective view of the preparation device in a configuration in which the first two lenses are ready to be immobilized by the two grippers of the means of reception and first and second transfers; FIG. 12 is a perspective view of the preparation device in a configuration in which the first lens is, after a first transfer, brought into measuring position in alignment with measuring means for the automatic measurement of the centering characteristics of this device. FIG. 13 is a perspective view of the preparation device in a configuration where the first lens is, after a second transfer, brought into the intermediate position, with a view to its probing and its third transfer, facing the probing means, grasping and second transfer; FIG. 14 is a schematic side view of the lens with its optical axis and its boxing axis (defined later) associated; FIG. 15 is a perspective view of the combined probing, gripping and third transfer means alone; - Figures 16 to 18 are cross-sectional views of the automatic preparation device of Figure 15, the probing means, gripping and third transfer being shown in several successive configurations of probing the lens; FIG. 19 is an elevation view of the automatic preparation device in which the probing, gripping and third transfer means are in the probing configuration of the first lens to determine the relative height of a remarkable point such as the optical center. this lens relative to the measuring means to allow the precise calculation of a frontal power of the lens at the remarkable point considered; FIG. 20 is a perspective view of the preparation device in a configuration where the palletizing, gripping and third transfer means probing the contour of the first lens; FIG. 21 is a perspective view of the preparation device, similar to FIG. 19, in a configuration where the probing, gripping and third transfer means perform a new probing of this first lens in at least three points to determine the normal at the blocking point; FIGS. 22 to 24 are elevational views of the automatic preparation device, with partial sectioning of the probing, gripping and third transfer means represented in three successive configurations in order to immobilize the first lens along a gripping axis and blocking corresponding to a remarkable axis, said boxing axis (defined later), of this lens; FIG. 25 is a perspective view of the preparation device in a configuration where the first lens is in the course of third transfer by the probing, gripping and second transfer means from its intermediate position towards the trimming device; - Figures 26 and 27 are perspective views of the preparation device in successive configurations of its third transfer and integration of the first lens in the trimming device; FIG. 28 is a perspective view of the preparation device in a relay passage configuration, where the first lens is held by both the probing, gripping and third transfer means and by the locking and clamping means. rotating the clipping device; - Figures 29 and 30 are respectively perspective views and in longitudinal section of the first lens held between two nose, themselves engaged with two shafts and rotation of the shaper device; FIG. 31 is a perspective view of a magazine comprising a plurality of pairs of noses for enabling the immobilization of lenses of different sizes and / or coatings; - Figure 32 is a partial perspective view of the plate illustrating a variant of the reception means and first and second transfers with an optional lens centering pin; FIG. 33 is a perspective view of the automatic preparation device in a configuration where the first lens of the job is, after having been cut off and then transferred according to a fourth transfer, replaced by the third transfer means in the intermediate position on the means of welcome and first and second transfers; - Figure 34 is a perspective view of the automatic preparation device in a configuration where the first two lenses are brought to the unloading position by the reception means and first and second transfers; FIG. 35 is a perspective view of the automatic preparation device in a configuration where the reception and first and second transfer means are ready to receive a second pair of lenses of a second job, whereas the first lens of the first pair is further processed in the trimming device and the second lens of the same first pair is processed by the measuring means; FIG. 36 is a plan view of the front face of a progressive correction lens on which the conventional markings of this lens are reported; and FIG. 37 is a schematic view of an exemplary embodiment of the device for measuring the characteristics of a lens; - Figure 38 is a schematic front view of a frame of a pair of glasses positioned on the nose of a wearer; FIGS. 39 and 40 are front views schematizing the joint confrontation and centering of the two lenses of the same job in preparation; - Figure 41 is a schematic perspective view of the main components of the clipping means.
COMPONENTS OF THE AUTOMATIC PREPARATION DEVICE
As shown more particularly in FIGS. 1 and 2, the assembly preparation device 1 according to the present invention comprises several subassemblies mounted on a common frame: a measuring device 5 for the automatic measurement of various characteristics of the lenses L1 and L2 (which can be for example unifocal, multifocal with pellet (s) of near vision or intermediate with power discontinuity, or multifocal with progressive power addition) and in particular the measurement of local ophthalmic powers at remarkable points such as the optical center of a single lens or the reference points for near and far vision, and the measurement of at least one marking feature, such as a centering, , locating reference points for distant vision and near vision, of the lens; a device for trimming ophthalmic lenses; combined reception and first and second transfer means 2 designed and arranged to receive one or more ophthalmic lens jobs, for example a job of two lenses L1 and L2, and to circulate them between a loading position and unloading, a measurement position in which the ophthalmic lens is presented opposite the measuring device 5 for measuring its locating characteristics and an intermediate position for its support by the probing means, seizure and third transfer provided ci -Dessous; probing, grasping and third transfer means 7 designed and arranged for firstly palpating each ophthalmic lens in preparation and secondly for grasping this lens with a view to transferring it from the reception and first and second means; second transfers 2 to the clipping device 6; an electronic and computer system 100 designed for executing an automated processing method according to the invention; a cover 20 enclosing the assembly for its protection and having a restricted access door 26.
Measuring device The measuring device 5 of the present invention has several functions of measuring various characteristics of the lens. Among these various functions which will be described in detail later, there are two main functions which consist, for one, in measuring the local optical powers of the lens at remarkable points thereof, and for the other, in detecting and locating centering characteristics or location of the lens in order to establish or properly position the lens in a known global repository of the device.
In the exercise of its first function, the measuring device 5 operates without contact, by overall map imaging, but is completed by the probing means 7 which, as we shall see in detail, perform a probing of the lens for to provide a geometric information combined with the optical information delivered by the measuring device 5. This probing operates, in the example described hereinafter, by contact with the lens. But it goes without saying that the skilled person may substitute a contactless probing operation equivalent to a geometric position statement.
Beyond the embodiment shown below, the measuring device can be of any type according to which the lens is presented between the illumination means and the analysis means to obtain an overall measurement of one or more of its optical characteristics at a plurality of points over most of its extent. The overall optical measurement can be obtained by deflectrometry (Hartmann type, moiré, etc.), interferometry, wave propagation, etc. The user interface can then display not only the optical or reference center, but also power and / or power and / or axis maps at one or more remarkable points of the lens.
To understand the second centering function exerted by the measuring device 5 and more generally even the problem solved by the invention, it is necessary to remember that, when mounting an ophthalmic lens on a frame, it is important for the visual comfort of the wearer to ensure the proper positioning of the lens relative to the eye which it corrects a defect of refraction or accommodation.
Overall, an ophthalmic lens is centered when, on the one hand, the optical center (for unifocal or multifocal lenses with power discontinuity) or the reference center (for progressive lenses) of the ophthalmic lens provided during the design and on the other hand, the pupillary center of the eye is superimposed or otherwise formulated when the line of sight passes through the optic center or reference center of the ophthalmic lens. Centering therefore results from the approximation of two geometric-optical data: the pupil morphology of the wearer and the position on the lens of the optical center or the reference center. The lens must also, to exercise the desired optical function, be properly oriented around its optical axis.
With regard more particularly to ophthalmic lenses with progressive power addition, it is known that, during its manufacture, any progressive lens is provided with temporary markers in the form of a paint marking and permanent markers in the form of engravings. Provisional marks allow convenient centering of the lens prior to mounting. The permanent markings make it possible to identify, on the patient's frame, the nature of the progressive ophthalmic lens, the value of the addition as well as to verify or restore, after erasure of the temporary marks, the exact centering of said lens. It is understood that the provisional marks will be erased by the optician before the delivery of the glasses to his client and they can, if necessary, be restored from permanent markings engraved remaining on the ophthalmic lens.
More precisely, as shown in FIG. 36, the provisional markers usually comprise: a so-called mounting or centering cross 11, embodying the center of the far vision zone, intended to be positioned facing the center of the pupil's pupil when he looks to infinity right in front of him; it makes it possible to position vertically and horizontally the power progression of the lens L1 with respect to the eye, so that the wearer can easily find, as expected by the designer of the lens, the corrective power that he needs in his vision. far, in intermediate vision and near vision; a central point 12 situated, according to the types of lenses, 2 to 6 mm below the mounting cross 11 and which locates the "optical center" of the lens L1; this "optical center" is conventionally, for a progressive lens, the prism reference point where the nominal prismatic power of the lens L1 corresponding to the wearer's prescription is measured; a circle 13 for measuring the far vision power of the lens, located in the upper part of the lens L1, just above the mounting cross 11, and which locates the reference point for far vision ; it is therefore the place where a frontofocometer should be placed to measure the far vision power of the lens L1; a circle 14 for measuring the power of near vision of the lens, situated in the lower part of the lens L1 and which surrounds the center or reference point of the near vision zone; this center is off-center on the nasal side by 2 to 3 mm and the distance separating it from the mounting cross 11 constitutes the nominal length of the progression of the lens L1; one or more lines marking the horizontal of the lens L1 and which will be used for centering.
As also shown in FIG. 36, the permanent markers generally comprise: two small circles or signs 16 located on the horizontal of the lens L1 passing through the optical center and located systematically at 17 mm on either side of the center optical 12; these engravings make it possible to find the horizontal and vertical centering of the lens; a sign 17 making it possible to identify the mark and the exact nature of the progressive lens (for example V for Varilux) which is engraved under the small circle or nasal sign; a number with 2 or 3 digits representing the value of the addition (for example 30 or 300 for an addition of 3.00 D) which is etched under the small circle or temporal sign.
For the record, it will be remembered that, for multi-focus lenses having one or more lines of power discontinuity (delimiting for example a zone, called lozenge, near vision), these lines take the place of permanent markers.
The device 5 for automatically measuring the characteristics of an ophthalmic lens L1 is shown schematically in FIG. 37. This automatic measuring device comprises a support for the lens L1, here horizontal and constituted by the carousel of the means of reception and of first and second transfers 2 which will be described later. It is sufficient to understand here that these means of first transfer are able to bring the lens to be examined in a measurement position located opposite the measuring device and centered on the optical axis of the measuring device, as will be better explained later. . Below this measurement position of the lens L1, a transparent glass plate protects the inside of the device. On either side of this measurement position of the lens L1, the measuring device comprises, along a mainly vertical optical axis, on the one hand, illumination means 208 including an optical system 211 for developing a light beam directed to the lens L1 in measurement position and, secondly, means 210 for analyzing the image transmitted by the lens L1 in the measurement position.
The optical system 211 is arranged to define two possible optical paths 212, 213, switchable, that is to say activatable alternately, for said light beam. In the example shown, the illumination means comprise at least two switchable light sources S 1, S 2, respectively corresponding to the two optical paths mentioned above. In other words, when the source S1 is on, the source S2 is off and vice versa. The two optical paths 212, 213 comprise a common portion 215 upstream of the lens L1, more particularly determined between a semi-reflecting oblique mirror 218 and the lens L1. This mirror materializes the intersection of the two optical paths. The mirror 218 can be replaced by a separator cube or a removable mirror.
A first mask 220 forming a Hartmann matrix or the like is placed on only one of the paths (the path 212), in a location such that it occupies a predetermined position with respect to a vertical main optical axis 225 of said means for analysis 210. This optical axis 225 is in fact the common axis IiB of some lenses of the optical system centered with respect to the source S1 and an optical receiver 228 forming part of the analysis means 210 located on the other side of the lens L1 in measurement position. The analysis means also comprise a translucent screen 229 frosted interspersed perpendicularly to this optical axis 225 between the lens L1 in measuring position and said optical receiver 228. The latter may be a matrix sensor or a camera with lens. If the optical receiver is a matrix sensor, a lens 231 is added thereto and, optionally, a diaphragm not provided for in the illustrated example. If the optical receiver is a camera, these elements are replaced by the very purpose of the camera. The translucent screen 229 is preferably frosted glass surface or the like. It is a disk mounted rotating and rotated by a motor 235 around the optical axis 225.
Returning to the optical system 211 linked to the sources S1 and S2, the first light source S1 among these two sources is a so-called point source capable of providing a divergent beam illuminating the first mask 220 along the first path 212, before being reflected sweating the mirror oblique 218 to take the common portion of optical path 215 and thus illuminate the ophthalmic lens L1. The oblique mirror 218 is at an angle of 45 with respect to the optical axis 225 so that the beam from the source S1 is reflected on this mirror and directed towards the ophthalmic lens L1. Downstream of the first mask 220, thus on the first optical path 212, the light emitted by the source S2 splits into a plurality of distinct light rays, the first Hartmann type mask 220 exerting its beam splitter function.
The source S1 may optionally be movable along the optical axis or an axis perpendicular to it, but illuminates in all cases, when activated, the first mask 220. The optical system further comprises a collimating lens 241. centered on the optical axis 225 and placed between the mirror 218 and the measured ophthalmic lens L1. This lens 241 makes it possible to generate a large parallel beam of light larger than that of the lens L1 and to image the first mask 220 on the surface of the ophthalmic lens LI.
A second light source S2 is arranged to illuminate the lens LI in measurement position via the second optical path 213, excluding the first mask 220 forming Hartmann matrix. This second light source passes through the semi-reflecting mirror 218 which materializes the intersection of the two optical paths 212, 213. This source S2 is a point source capable of providing a divergent beam directed towards the mirror 218. The axis of the beam generated by the source S2 is perpendicular to the beam generated by the source S1 upstream of the mirror 218 and passes through this mirror without being deflected. It then illuminates the ophthalmic lens L1 without having undergone any beam separation by any separating element of the Hartmann mask type or the like.
A second mask of Hartmann type 240 or similar beam splitter is disposed downstream of the ophthalmic lens L1, that is to say between this lens and the image analysis means 210. In this case, the mask 240 is located below the protective pane 203, adjacent thereto. This second mask 240 is engageable and disengageable at will, under the control of the electronic and computer system 100.
In practice this second mask can be made in the form of a transparent liquid crystal display (LCD) or the like, as in the example illustrated.
It may also consist of a permanent passive mask mounted movable relative to the ophthalmic lens, so as to be able to fade to release at least part of the ophthalmic lens when this part must be examined without this second mask, as explained later.
Under these conditions the term "engageable" and "disengageable" mean that the mask in question operates or not its function of separation of the light beam upstream or downstream of the lens on all or part of the surface of the ophthalmic lens. It is understood that, in practice, the engagement or the disengagement of the mask can take on a different reality depending on the type of mask used.
When the mask is of the passive type and consists for example of a support of one or more patterns embodied on this support, such as a grid or a perforated plate, the term disengageable means in particular retractable or retractable mechanically, in whole or in part, the mask then being mounted movable relative to the lens (whether it is itself mobile or the lens is movable and the mask is fixed) to allow clearance of at least a portion of the corresponding surface of the lens in view of its illumination or its direct reading, with the complete light beam, without separation of this beam. The term disengageable can also mean optically shuntable as is the case for the mask 220.
When the mask is of the active type and consists for example of a dynamic display screen such as a CRT or LCD screen, the term disengageable means deactivatable: the control electronics of the screen extinguishes any reason for separation on at least one zone of this screen corresponding to the zone to be read without beam separation of the lens.
In the example illustrated, the mask 240 is active LCD type, and therefore deactivatable, and the mask 220 is passive (hard) and optically shuntable (by the two alternative optical paths 212 and 213). However, one could alternatively provide that the mask 220 between the source and the lens is of active type, such as an LCD screen, activatable and electronically deactivatable, such as the mask 240 located between the lens and the frosted screen.
In use, the measuring device thus composed is capable of adopting three states corresponding to three modes of operation: State 1: the source S1 is activated and illuminates the lens L1 through the first mask 220 (this first mask being in this way "activated"), the source S2 being extinguished and the second mask 240 being deactivated; in other words, the first mask 220 is engaged alone.
State 2: the source S2 is activated and the second mask 240 is activated, the source Si being off (the first mask 220 is thus somehow "deactivated"); thus, the second mask 240 is engaged alone.
State 3: only the source S2 is activated, the source S1 and its mask 220 associated with being deactivated and the second mask 240 being at least partially deactivated (or retracted); thus, the two masks 220, 240 are disengaged simultaneously.
In state 1, the source S1 and its associated mask 220 are activated and used to correct the reading error and reposition the marks, marks or indicators (engraving, marking, segment) of the front face of the lens seen on the screen. screen 229 by the sensor 218, due to prismatic deviations through the ophthalmic lens L1.
In state 2, the source S2 and its associated mask 240 are activated together, while the source S1 is deactivated, to perform a global analysis of one or more optical characteristics at a plurality of points over the entire extent of the lens, in order to measure this or these optical characteristics in one or more isolated noticeable points (such as the reference points for the near vision and for the distant vision of a progressive lens or the optical center or centers of a lens unifocal or multifocal with power discontinuity) or, possibly, to map the L1 ophthalmic lens (in particular measurement of power / astigmatism at several points of the lens) and the determination of the optical center of the ophthalmic lens L1 when that This is of the non-progressive type.
In state 3, source S2 is activated alone, while source S1 and second mask 240 are deactivated, for the determination of printed marks, relief engravings and segments (bifocal and trifocal glasses) requiring at least locally an unobstructed vision of the ophthalmic lens.
The light sources mentioned S1, S2, above may be light-emitting diodes (LEDs) or laser diodes preferably associated with respective optical fibers.
We will now describe how the measuring device can be used to determine a certain number of characteristics of the ophthalmic lens LI in measurement position.
First function: identification of the ophthalmic lens It is useful to be able to recognize, before anything else, the type of ophthalmic lens analyzed (monofocal, multifocal or progressive) to avoid errors. To do this, the source S2 is used in conjunction with the second mask 240 forming a Hartmann matrix. The measuring device is in its state 2 or in its state 3. The beam following the second optical path 213 is transformed by the second mask 240 into a plurality of individualized fine rays corresponding to the configuration of the mask. Each of these spokes strikes the front face of the lens L1 parallel to the optical axis 225, that is to say generally perpendicular to the median plane of the ophthalmic lens L1 (so in this case vertically, the ophthalmic lens LI being maintained horizontally by the means of reception and first transfer 2, as we will see later). These rays are deflected by the ophthalmic lens L1 and are visualized in the form of light spots on the rotating frosted screen 229. The frosting is imaged on the matrix sensor associated with the telecentric system or that of the camera, and the tasks are analyzed by a electronic and computer processing system (associated or integrated with the electronic and computer system 100) which determines their displacement.
If the lens is of the unifocal type, the displacement of the points of the mask (that is to say the light spots which appear on the frosted screen) after deviation by the lens is in radial progression from the center to the periphery, compared to positions of the same points when no ophthalmic lens is present on the optical axis of the measuring device. The positions of the points of the Hartmann mask on the screen when no lens is present next to the measuring device are measured during a calibration phase.
For a converging lens, the tasks are close to the optical axis, especially since the ophthalmic lens to be measured is powerful.
When the analyzed lens is progressive, the distribution of the points does not have axial symmetry.
Therefore, measuring a displacement of this kind makes it possible to determine the type of lens.
Other means and methods for determining the type of lens are well known to those skilled in the art and may be used in the context of the present invention in place of the example given above.
Second function: determination of the progress line of a progressive lens In the measurement conditions indicated above (state 2), it is observed that for a progressive lens, the displacement of the points varies along a line called "line of progression" . To determine this progression line, the direction of the power gradient is determined by calculation by calculating the power at different points of the lens, for example according to the method which will be indicated below. This direction is the progression line. It is therefore possible to measure and calculate the orientation of the progression line, which is one of the important characteristics of a progressive lens. It should be noted that these calculations are carried out from two sets of data, on the one hand the configuration of the points of the second Hartmann mask 240 on the frosted screen when no ophthalmic lens is present on the optical axis of the measuring device and secondly the corresponding configuration of the same points when it results from a deviation of all the rays by the ophthalmic lens L1.
Third function: determination of the optical center for a non-progressive lens If the ophthalmic lens L1 has been identified as being of the unifocal type, it is easy to determine the position of the optical center of this lens. Since the device is still in its state 2, it suffices to compare the points of the reference mask (appearing on the frosted screen 229 when no lens is present on the optical axis of the measuring device) and the corresponding points of the mask visualized on the frosted screen after deflection by the lens. In principle, the point of the second mask 240 which has not been deviated corresponds to the position of the optical center. Since there is generally no undifferentiated ray, an interpolation is made from the least deviated rays, for example by applying the least squares method on a polynomial model.
Fourth function: calculation of the power and astigmatism of the ophthalmic lens It is known that for a unifocal lens, the distance between the focus and the rear face of the ophthalmic lens represents the frontal power.
The position of the rear face of the ophthalmic lens LI is given a posteriori by means of probing with the probing, gripping and second transfer means 7, as will be better explained later. To determine the focus, the device is still in its state 2 and the image on the frosted screen of the second Hartmann matrix mask 240 is still used. To do this, we compare the position of the corresponding points between the calibration image (taken before positioning the ophthalmic lens) and the image after interposition of the ophthalmic lens. Given the distance between the mask 240 and the screen 229 (known by construction), the calculation is made of the angle of deviation of the light rays resulting from the beam separation produced by the mask 240.
For several neighboring points, the position and direction of the light rays are compared, which makes it possible to calculate the position of the focus on the optical axis (and therefore its power, which is the inverse of the distance from the focus to the ophthalmic lens ) and the astigmatism of the ophthalmic lens (value and axis of astigmatism) if there is astigmatism. These measurements are local and can be repeated on different areas of the ophthalmic lens, which allows to obtain a power card of the ophthalmic lens.
Fifth function: determination of the centering point and the axis of the horizontal for a progressive lens It is known that one can consider that at any point of the ophthalmic lens, the front face and the rear face make an assimilable angle to a prism.
On the other hand, in a progressive lens, the addition is defined as being the difference between the maximum power and the minimum power of the ophthalmic lens.
The point of reference of the prism is generally defined as the point where the prism of the ophthalmic lens is equal to the prescribed prism. On a progressive lens, the prism reference point (PRP) is comparable to the optical center of a unifocal lens (and is sometimes so called by abuse of language) and is located in the center of a segment separating two landmarks engraved on the front of the lens. Most often, this point is also marked by a specific printed marking.
Whatever the case may be, the location of the prism reference point or any remarkable point used for centering the ophthalmic lens L1, when this lens is progressive, takes place in the state 3, illuminating the lens L1 to from the light source S2, that is to say by avoiding the first mask Hartmann 220. The image transmitted by the ophthalmic lens L1 appears on the etched glass 229 and is perceived by the optical receiver 228. The reading is accompanied an appropriate image processing to identify the engraved marks or markings and determine their positions in a known fixed reference system of the electronic and computer system 100. This visualization of the engraved markings or markings and the determination of the prism reference point then allows to determine the centering point of the progressive lens (mounting cross) on which the position of the center of the pupil of the eye of the wearer must coincide with the ax e horizontal which gives the orientation of the ophthalmic lens in the mount.
Sixth function: determination of the position of the segment in the case of a bifocal lens The source S2 alone without a mask (state 3 of the measurement device) is still used which makes it possible to visualize the image of the ophthalmic lens L1 on the frosted screen. Appropriate image processing makes it possible to better observe the variations in light intensity on the screen and consequently to obtain a clear outline of the limits of the segment, and to determine its position with precision.
Seventh function: Determination of the shape and dimensions of the ophthalmic lens These characteristics are determined by illuminating the ophthalmic lens from source S2 without a Hartmann mask (state 3 of the measuring device) and by performing an appropriate image processing to better discern the contours of the ophthalmic lens. Before trimming, the ophthalmic lens is generally circular and this analysis is mainly to determine its diameter. However, it may happen that the ophthalmic lens already has a shape close to that of the frame for which it is intended. The image processing makes it possible to know the shape and dimensions of the non-circular ophthalmic lens. The determination of the shape and dimensions of the ophthalmic lens makes it possible to verify that it is sufficiently large to fit into the frame or shape chosen.
Eighth function: correction of the reading errors due to the prismatic deviations induced by the measured ophthalmic lens. It should be noted that for all the parameters indicated above which are acquired from the illumination of the ophthalmic lens by the source S2 alone, that is to say, excluding the two Hartmann masks 220 and 240, it is possible to reprocess the measurements to "postpone" the positions of the marks, engravings or segment read on the frosted screen, at the front face of the ophthalmic lens. The source S2 makes it possible to see the marks, engravings or segment, but does not make it possible to determine their real positions on the front face of the ophthalmic lens. The source S1 associated with the first matrix 220, on the other hand, makes it possible to calculate the precise position of these elements acquired with S2 on the front face of the ophthalmic lens.
We proceed as follows. Suppose we consider the light spot A on the frosted screen 229 corresponding to one of the holes of the Hartmann mask. The corresponding light beam strikes the front face of the ophthalmic lens L1 at A '. In a first step, the source S2 is turned on and the corresponding image which appears on the frosted screen is stored. Then, we turn on the source S1 and turn off the source S2. The image of the Hartmann mask thus appears on the frosted screen 229. By construction, the height of each hole of the Hartmann mask is known (distance from the hole relative to the optical axis 225). Consequently, for a given radius, the height of the radius corresponding to its point of entry on the front face of the ophthalmic lens L1 is known. That is to say, we know the height of the point A 'corresponding to the point A. Therefore, we can assign to the point A a correction that determines A'. We can therefore find the position on the lens itself, any mark read on the frosted screen, which increases the accuracy of this measurement. In other words, the use of the Hartmann mask 220 in connection with the light source S1 (said Hartmann mask being placed upstream of the ophthalmic lens L1) makes it possible to improve all the measurements that are carried out by illuminating the lens from a source S2 borrowing an optical path excluding said mask.
Ninth function: correction of errors in the measurement of the power of all types of lenses and the centering and orientation of single-vision lenses The combination of the two masks 220 and 240 located on either side of the lens makes it possible to partially correct the errors of centering, centering and power from a fault in positioning the lens.
It may indeed be that, for various reasons such as, for example, a defect in the positioning of the lens to be measured on the support plate 30 at the time of its loading or else a misalignment of the measuring device with respect to the plate 30 for supporting the lens to be measured, the lens is opposite the measuring device with its axis forming a non-negligible angle with the main axis 225 of the measuring device. This lack of horizontality in the positioning of the lens to be measured generates optical aberrations on the wavefront near the point where it is desired to carry out the measurement (which may be the optical center or any remarkable point of the lens where the it is desired to measure an optical characteristic) as well as an offset of the ray passing through this point. These optical aberrations or this offset of the rays at the point of interest distorts the measurements of the optical characteristics, and in particular the local optical powers and axes of the lens when this lens is of any type and in particular with progressive variation of power (s). as well as the position of the optical center and the orientation of the main axis of astigmatism when the lens is of unifocal type.
It is thus in particular that an error is made in measuring the position of the optical center of a unifocal lens which is approximately equal to the product: and where i is the angle of inclination of the lens. optical axis of the lens with respect to the main axis of the measuring device, that is to say in this case with respect to the vertical, and di is the distance between the main image plane and the convex front face of the lens (when this face is as in this case the upper face facing sources S1 and S2).
Thanks to the possibilities offered by the combination of two beam splitter masks located on either side of the lens, it is possible to measure and therefore correct, at least partially, this error. We proceed as follows.
The optical center is measured in accordance with the third function explained above, with the state 2 of the device, the second mask 240 being engaged alone.
The offset e2 resulting from the inclination error i of the lens possibly undergone by a beam is then measured at this point, with the state 1 of the device, the first mask 220 being engaged alone.
If the offset is zero, we deduce that the lens is properly positioned, without horizontal defect (zero inclination i = 0).
Otherwise, the angle of inclination i of the optical axis of the lens to be measured is approximately calculated by the following formula: i = e2 / d2 where e2 is the measured offset and d2 is the distance (mean, power dependent) of the measured lens) between the object main plane and the image main plane of the measured lens.
We then apply a correction equal to the error el = i.dim on the measured position of the optical center, where dim is an averaged estimate, in particular according to the power of the lens, the distance between the main image plane and the face convex front of the lens (when this face is as in this case the upper face facing sources S1 and S2). 28
Dismantling device The trimming device 6 can be made in the form of any cutting or material removal machine adapted to modify the contour of the ophthalmic lens to adapt it to that of the frame or "circle" of a frame selected. Such a machine may consist for example of a grinder, a laser cutting machine or jet water, etc. In particular, it may be, as in the illustrated example, a grinder conventionally used for trimming ophthalmic lenses of plastic or mineral glasses. Such a grinder comprises mainly, on a frame, a machining station, which is equipped with one or more grinding wheel (s) and one or more grinding wheel (s) and chamfering rotatably mounted around a axis under the control of a drive motor, and a carriage, which is equipped parallel to the axis of said grinding wheels, two coaxial shafts clamping and driving in rotation of the lens. These shafts are adapted to axially grip the lens to be treated and are rotatably mounted under the control of a drive motor.
The carriage is mounted movably on the chassis, on the one hand transversely to the axis of the grinding wheels, under the control of support means urging it towards said axis, and, on the other hand, axially parallel to the axis of these wheels, under the control of appropriate control means.
For its transverse displacement relative to the axis of the wheels, which is necessary for the application of the ophthalmic lens to be treated against them, this carriage can for example be pivotally mounted on a shaft parallel to this axis (the carriage is then usually called "rocker"), or be movably mounted in translation perpendicular thereto.
More precisely, in the example shown diagrammatically in FIG. 41, the trimming device 6 comprises, in a manner known per se, a grinder 610. This grinder comprises, in the present case, on the one hand, a flip-flop 611, which is mounted freely pivoting about a first axis A1, in practice a horizontal axis, on a frame 601 associated with the frame of the entire preparation device, and which, for the support and maintenance of an ophthalmic lens such as L1 to be machined, is equipped with two clamping and driving shafts 612, 613 aligned with each other along a second axis A2 parallel to the first axis A1 and duly driven in rotation by a motor also not shown, and, d on the other hand, at least one wheel 614, which is locked in rotation on a third axis A3 parallel to the first axis A1, and which is also properly rotated by a motor not shown. For the sake of simplicity, the axes A1, A2 and A3 have only been shown schematically in broken lines in FIG.
In practice, the grinder 610 comprises a train of several grinding wheels such as 614 mounted coaxially on the third axis A3, for roughing and finishing of the ophthalmic lens L1 to be machined, and the assembly is carried by a carriage, also not shown. , which is movable in translation along the first axis A1. These different grinding wheels are each adapted to the material of the cut-out lens and to the type of operation performed (roughing, finishing, grooving, etc.).
The wheel 614 (or more precisely the entire wheel set) is movable in translation along the axis A3 and is controlled in this translation by a motorization not shown.
As regards, in practice, an automatic grinder, commonly known as a digital grinder, the grinder 610 according to the invention further comprises a link 616, which, articulated to the frame around the same first axis A1 as the latch 611 to the one of its ends is articulated, at the other end, along a fourth axis A4 parallel to the first axis A1, to a nut 617 mounted movably along a fifth axis A5, commonly called restitution axis, perpendicular to the first axis Al, with, intervening between this link 616 and the flip-flop 611, a contact sensor 618. T was noted the pivot angle of the flip-flop 611 about the Al axis relative to the horizontal. This angle T is linearly associated with the vertical translation, denoted R, of the nut 617 along the axis A5.
For example, and as shown diagrammatically in FIG. 41, the nut 617 is a threaded nut threadedly engaged with a threaded rod 638 which, aligned along the fifth axis A5, is rotated by a motor 619.
For example, also, the contact sensor 618 is constituted by a Hall effect cell.
When, duly sandwiched between the two shafts 612, 613, the ophthalmic lens to be machined is brought into contact with the grinding wheel 614, it is the object of effective material removal until the flip-flop 611 abuts against the link 616 following a support which, being at the contact sensor 618, is duly detected by it.
Alternatively, it can be provided that the flip-flop 611 is directly articulated to the nut 617 mounted movably along the restitution axis A5. A strain gauge is associated with the rocker to measure the machining advance force applied to the lens. Thus, during the machining, the grinding advance force applied to the lens is continuously measured and the progression of the nut 617, and therefore of the lever 611, is controlled so that this effort remains below maximum setpoint. This setpoint is, for each lens, adapted to the material and the shape of this lens.
Anyway, for the machining of the ophthalmic lens LI according to a given contour, it suffices, therefore, firstly to move accordingly the nut 617 along the fifth axis A5, under the control of the motor 619, and, secondly, to jointly rotate the shafts 612, 613 about the second axis A2, in practice under the control of the motor that controls them, so that all the points of the contour of the ophthalmic lens LI are successively concerned .
The electronic and computer system 100, duly programmed for this purpose, coordinates this double operation.
The foregoing provisions are, moreover, well known in themselves, and, not falling within the scope of the present invention, they will not be described in more detail here.
Combined means of reception and first and second transfers The means of reception and first and second transfers 2 take the form of a carousel which is more particularly described with reference to Figures 4 to 8 and which comprises: - a plateau of loading and unloading 30 mounted on the common chassis to rotate, under the control of control means (in this case an electric motor not shown) controlled by the electronic and computer system 100, about an axis of rotation substantially through its center and perpendicular to the plane of this plateau; a support frame 31 integral with the common frame; reception seats 34, 35 on which the lenses L1 and L2 are intended to rest when they are loaded on the plate 30.
- On the loading and unloading platform 30, at least three loading places 36 to 38 and at least four unloading places 41 to 44.
immobilization means 32 of the lenses L1 and L2 loaded on the plate 30 at the loading places 36 to 38.
In the illustrated example, the loading places 36 to 38 are constituted by a corresponding number of indentations or recesses. These three notches 36 to 38 are identical and each have a substantially circular shape of diameter slightly greater than the standard (about 70 mm) of the L1 and L2 lenses to be cut. The three indentations are arranged emerging on the periphery of the loading and unloading tray 30. These openings allow access to at least two seats 34, 35 on which the lenses to be cut. Next to the loading places 36 to 38 are articulated clamps 32 constituting the means for immobilizing the lenses (Figures 6 to 8).
In accordance with the figures and in particular with FIG. 5 which gives in itself a detailed description of the plate 30, the four places of unloading 41 to 44 are constituted by recesses or bowls formed on the surface of the plate 30. These hollow or depressions are of circular shape of diameter always greater than that of the lenses LI and L2 after trimming.
Virtually radial slots 45 are provided from the center of each unloading cavity 41 to 44 to the peripheral edge of the plate 30 on which these openings open. These lights are intended to allow the depositing of the lenses, after trimming, by the means of third and fourth transfer, as we will see later.
Each lumen 45 is arranged to form a slideway for receiving an associated tab 49 which is mounted in the lumen 45 to which it is associated to slide between an outer covering position of the light 45 concerned, as illustrated by the position of FIG. tab 49 associated with the unloading footprint 42 in Fig. 5, and an erase inner position in which it retracts toward the center of the tray 30 beneath the tray 30, as illustrated by the position of the tongue 49 associated with the Unloading footprint 41 in FIG. 5. Each tongue 49 is connected to a return spring located under the plate 30 (not visible in the figures) which tends to bring it back to the outer covering position of the light 45.
Alternatively, it may also be provided that the cover tabs 49 are mounted on the carousel tray for pivoting between 3: 2 a retracted position and a covering position of each corresponding light. The pivoting of each tongue can then advantageously be controlled by the same actuating mechanism as the clamps.
Alternatively, it may further be provided that the recesses or cuvettes 41 to 44 are completely closed without presenting any day so as to be watertight.
Nevertheless, whether the recesses or cuvettes 41 to 44 have a closing tab or are closed, it is observed that they are arranged to collect the drops of lubricant from each lens after its trimming. This avoids wetting the constituent parts, possibly subject to corrosion or electronic or requiring cleanliness as is particularly the case of the optical measuring device 5.
Preferably, a first loading place 36 is diametrically opposed to the other two loading places 37, 38 themselves located adjacent. The four unloading spaces 41 to 44 are grouped in pairs. Thus, a first pair of unloading places 41, 42 is interposed between the two loading places 36, 37 while the other two unloading places 43, 44 are located between the loading places 36 and 38.
This provides a very compact loading and unloading platform 30 for maximizing the number of pairs of lenses that can be processed with a small footprint. The loading places and the unloading places are regularly distributed around the periphery of the plateau and are all substantially of the same surface.
The locking means 32 of the lenses comprise clips 46 to 48 which are each located directly above the loading places 36 to 38. These clips each comprise two legs 50 and 51 whose feet 53 are mounted articulated on a hub 54. and whose free ends 55 are provided with articulated fingers 56 in the general shape of V. The hub 54 is rotationally integral with the loading and unloading platform 30 so that the clamps 46 to 48 are rotated simultaneously with the plate. Each of the clamps thus remains opposite each of the loading places 36 to 38 respectively.
The clamps 46 to 48 are biased in the closed position by an elastic element such as a return spring 57 placed between the feet 53 of the two branches 50, 51 of each clamp.
Furthermore, the three clamps 46 to 48 are driven into the open position, in which they can grip a lens, by a particular drive mechanism 58. As is more particularly visible in Figures 7 and 8, this drive mechanism 58 consists of a system of gears and belts for controlling the rotation of three heads 60 each located in the vicinity of a respective foot 53 of the clamps. These heads are intended to cooperate each alternately, in the manner of a screwdriver head, with complementary actuating forks 61 each carried by the clamps 46 to 48.
This drive mechanism 58 is fixedly mounted on the frame 31 and therefore does not rotate with the plate 30 and the hub 54. It comprises three sets each consisting of a motor pulley 62, a toothed wheel 63 and a belt 64 stretched between this pulley and this wheel. The toothed wheel 63 carries the finger 60 itself located on the circular path of the fork 61 with which it cooperates.
Thus, when the loading and unloading tray 30 and the clamps 46 to 48 are brought to a marked position, also called loading / unloading position, the forks 61 are brought into cooperation with the heads 60, each of the heads 60 penetrating lathe in turn in the corresponding fork 61. The motor pulleys 62 are then rotated to cause rotation of the toothed wheels 63 and thus the forks 61 in engagement with the heads 60, allowing the opening of the clamps 46 to 48 by spacing the branches 50, 51 to 50. against the springs 53.
For the sake of simplification of the mechanism, the feet 53 of the arms 50, 51 of each of the clamps 46 to 48 cooperate with each other by gearing. For this purpose, as can be seen in FIG. 8, the feet 53 each have a toothed arc 65 turned towards the neighboring foot 53. Thus, it is sufficient that the fork 61 is carried by one of the two branches 50, 51 of a clamp for the two branches are moved and cause the opening of the clamp.
It is therefore understood that, each of the clamps 46 to 48 being biased in the closed position by its spring 57, the actuating fork 61 for controlling the opening of the clamp and arranged to engage in a specific position of the carousel 2, and only in this position, with the corresponding complementary actuating head 60 of the drive mechanism. It will be observed that this drive mechanism 60 to 65 is not loaded on the carousel 2 but is instead fixed, associated with the frame of the device. As a result, only the on-board clamps 46 to 48 rotate with the carousel, so that any mobile electrical connection is avoided. In addition, the carousel, thus lightened, has a lower inertia facilitating its precise control in rotation.
Furthermore, the fingers 56 of the clamps 46 to 48 each have an inner face 56.1 for the gripping of lens, which is curved in shape extending in a substantially vertical plane. The height of this finger gripping face is sufficient relative to the thickness of the lenses so as to firmly grip said lenses by their edge. For example, a height of 10 to 20 mm can be provided which is suitable for all prescriptions. The lower flank 68 of the fingers 56 is provided with an aliasing 69. Moreover, as can be seen in FIG. 6A, the merlons 68.1 of this aliasing of the lower flank 68 of each finger 56 form a horizontal inner projection arranged to form a groove. scraper tooth 68.1 shaped inclined ramp for picking the lens when the clamps tighten on them.
As shown more particularly in FIGS. 4 and 6, the seats 34, 35 each have an upper face 70 turned towards the loading and unloading platform 30. When they are loaded onto the plate 30, the lenses to be cut are intended to rest on the upper face 70 of each of the two seats 34, 35. Advantageously, in recess of the upper face 70 of each seat, is formed a central groove 71 arranged so that the upper face 70 is divided into two bearing zones , one outer 72 and the other inner 73, for the lenses, on either side of the central groove 71. This central groove is curved in shape whose center of curvature substantially corresponds to the center of rotation of the hub 54 carrying the clamps 46 to 48 and the plate 30. The depth of the central groove 71 is adapted so that at least a portion of the aliasing 69 moves within this groove when closing and the rotation of the tongs. Advantageously, the depth of the groove 71 is substantially equal to one third of the height of the fingers 56 of the clamps 46 to 48. Thus, when they are closed, the clamps 46 to 48 engage with the edge of the lens on any its thickness and the flanges of the fingers 56 overflow even downwards, that is to say toward the bottom of the groove 71. This arrangement ensures a secure and firm grip of the lens, even when it presents a small thickness.
To better ensure the stable and horizontal seating of the lens, especially when it is small as the right lens in Figure 6, two beads 75, 76 are formed in the bottom of the central groove 71. 75.76 bead each have a crown edge located in the plane of the upper face 70 and thus serve as a plane support to the lens in addition to the bearing areas 72,73. These beads are mutually spaced and are in the form of a circular arc so as to cooperate with the recessed reliefs of the aliasing 69 of the lower surface 68 of the fingers 56 during the closure of the clamps 46 to 48. Alternatively, these beads may in in addition to having a second function: guiding the movement of the fingers 56 during closing and opening of the clamps 46 to 48.
In addition, the seats 34, 35 are mounted on the frame 31 so as to be vertically movable, like an elevator, between a high position in which the upper face 70 of the seats is in the vicinity of the fingers 56 of the clamps 46. 48, and a low position, wherein the upper face of these seats is spaced from said fingers 56. Thus, the seats 34 and 35 are in the high position when lenses are loaded on the plate 30 to be immobilized by the clamps, and are in the low position when the lenses were gripped by the clamps to be taken to the next station, namely the measuring device 5. In the low position, the seats 34 and 35 are erased to allow free movement of the clamps and lenses.
Preferably, the measuring device 5 and the probing, gripping and third transfer means 7 are located side by side and diametrically opposite to the access door 26. The measuring device 5 is at least partly located in line with the path traveled by the loading places 36 to 38 and unloading 41 to 44 so that the lenses L1, L2 remain carried by the loading and unloading platform 30 when determining their characteristics.
In addition, the trimming device 6 is placed adjacent to the loading and unloading tray 30, and the probing, gripping and second transfer means 7 are interposed between the measuring device 5 and this trimming device 6.
Combined means of palpation, gripping and third transfer After the determination of certain characteristics of the lens L1 by means of the measuring device 5 according to the method described at the beginning of the present description, the loading and unloading platform 30 is again rotated to bring, in a second transfer, the lens L1 facing the probing means, gripping and third transfer 7 (Figure 13). The lens L1 is then in said intermediate position.
It is indeed necessary, in order to correctly locate the lens L1, to complete the previous measurement by probing the lens. It is particularly interesting to know the height e of the lens relative to the measuring device 5 and an axis hereinafter boxing axis, noted AB and defined below with reference to FIG. 14.
It is recalled that the optical center CO of a lens is the point where there is no image-distorting prism. The optical axis AO is the axis perpendicular to the plane of the lens passing through the optical center CO. The height e is calculated by palpating the lens at the location of the optical center CO.
Furthermore, a point of gripping and locking of the lens on which the blocking will be made is defined. This point is chosen as being confused with a point called boxing center CB, well known to those skilled in the art, which is the point of intersection of the diagonals of the horizontal rectangle in which is inscribed the shape of the desired contour of the lens after clipping. in the configuration of the worn (defining the horizontality). This boxing center is determined by the measuring device 5 according to the measured locating characteristics of the lens and the parameters of the wearer's morphology and the geometry of the chosen frame. For one of the two main faces of the lens, in this case the convex front face, is defined a docking and blocking axis, called boxing axis AB as the axis substantially normal to the surface of the relevant face of this lens and passing through the boxing CB center.
The probing, gripping and third transfer means 7 are designed and arranged to achieve the docking of a locking nose against one of the two main faces of said lens (in this case the convex front face) in a relative movement of translation of the first nose with respect to the lens along the boxing axis associated with this face. This locking nose is applied to the convex front face by being brought into translation in the direction of docking AB, with rigid retention in this translation, without angular mobility.
As is more particularly visible in FIG. 15, the probing, gripping and third transfer means 7 take the form of a member or arm ensuring on the one hand the probing of the lenses L1 and L2 and on the other hand the handling of these lenses for transfer (third transfer) to the trimming device 6.
For this purpose, the probe arm, gripping and third transfer 7 has a wrist 81 movable relative to the common frame in five controlled axes, with, in the configuration illustrated in Figure 15, a horizontal translation along the X axis , a vertical translation along the Z axis three rotations around the X, Y, Z. The control of these mobility axes is achieved in this case by motorized electrical means. However, those skilled in the art may provide for the use of other control means such as pneumatic or other means. Whatever the nature, the control of these five axes of mobility is controlled by the electronic and computer system 100.
In practice, as shown in more detail in Figure 15, the wrist 81 is articulated on a bearing stub 80 so as to be pivotable relative thereto along the axes X and Y. The stub 80 is itself mounted mobile in vertical translation along the Z axis on a vertical beam 82 forming for this purpose slide. This vertical beam 82 is carried at its lower end by a turret 82.1 which is rotatably mounted along the axis Z on a carriage 84. This carriage 84 is mounted on a horizontal beam 83, associated with the common frame and forming a slide, for sliding according to the axis X. The beam 83 is for example integral with the frame 31.
These five degrees of freedom of the wrist 81 in the fixed frame of reference (X, Y, Z) are controlled by various electric motors controlled, via an electronic card of appropriate power, by the electronic and computer system 100. This is how the rotations wrist 81 relative to the stump 80 around the X and Y axes are respectively controlled by motors 105, 106. The vertical sliding of the stump 80 is controlled by a motor 107 associated with the beam 82 and driving a screw 108 engaged in a nut 109 The rotation of the turret 82.1 carrying the vertical beam 82 around the vertical axis Z is controlled, via a belt 111, by a motor 110 whose body is integral with the carriage 84. Finally, the horizontal sliding of the carriage 84 is controlled by a motor 112 associated with the horizontal beam 83 and driving a screw 113 engaged in a nut 114 secured to the carriage 84.
To allow the separate probing functions on the one hand and gripping on the other hand, the wrist 81 of the arm 7 is provided with probing means 85 and gripping means 86 which are separate and independent of each other.
The probing means 85 are arranged to palpate independently or jointly the two main faces (front or convex 8 and rear or concave 9) of the lenses L1, L2. For this purpose, these probing means 85 comprise two branches 90 and 91 which are substantially rectilinear and which each end with a free angled end forming a probing nose 92, 93. The two mouthpieces 92, 93 of the two branches 90, 91 point towards each other so as to be brought into contact with the front faces 8 and rear 9 respectively. On each of the two nozzles 92 and 93 are mounted mechanical feelers known in themselves, operating by simple mechanical contact.
One and / or the other of the two branches 90 and 91, in this case the two branches 90 and 91 (see Figure 16 to 18) are movable in translation on the wrist 81. This translation allows to remove or The translations of the branches 90, 91 are respectively controlled independently of one another by encoder electric motors 180, 181 integrated in the wrist casing 81 and controlled by the electronic and computer system 100. The drive in translation and the permanent monitoring of the position of the branches 90, 91 by the electric motors 180, 181 are produced by means of a gear mechanism 182, 183 and rack 184, 185, each pinion 182, 183 being driven by the corresponding motor 180, 181 and the associated rack 184, 185 being secured to the branches 90, 91.
The gripping means 86 take the form of a locking clamp which consists of an upper jaw 95 and a lower jaw 96 movable in translation or pivot facing each other. In the illustrated example, the lower jaw 96 is movably mounted on the wrist 81 to slide on a rail 87 in the same direction of translation as the probe branch 90 and is for example driven in translation through a screw-nut mechanism 99 driven by an encoder motor integrated in the wrist casing 81. The upper jaw 95 is itself fixedly mounted on the wrist 81.
The jaws 95, 96 are of substantially rectilinear shape, generally parallel to the probing branches 90, 91, and are provided at their free end with means for releasably fastening by clip (clipping means) 97, 98 which here have the form of an open elastic ring C-shaped forming a clip. These clipping means are intended to accommodate noses 101, 102 for gripping and locking the lens.
The pair of noses 101, 102 thus mounted at the end of the gripping jaws 95, 96 makes it possible to perform the gripping and, later on the clipping means, the sandwich locking of a lens. In general, each nose has on the one hand axial fixing means and on the other hand transverse fixing means. Both noses are transferred, by means of the probe arm, gripping and second transfer 7, with the lens that they carry or block, from the carousel of reception and first transfer 2 to the device of clipping 6. II s is the third transfer of the lens concerned, as is better explained further in the context of the description of the preparation process.
However, attention is now drawn to an important characteristic of double interoperability of each nose: the transverse fixing means are arranged to cooperate with the arm 7 and the axial fixing means are arranged to cooperate with the shafts 612, 613 of clamping and rotating drive the grinder. The noses 101, 102 thus have a dual function. When they are associated with the arm 7, they constitute gripper tips for gripping and transferring the lens. When they cooperate with the shafts 612, 613 of the grinder, they constitute stops for locking and driving in rotation of the lens. We understand the major advantage of this third transfer of the lens operated with the nose in engagement with the lens: it avoids any loss of reference.
As shown in particular in FIGS. 28 to 31, each gripping and locking nose 101, 102 has a general shape of a mushroom of revolution about an axis which, in use, is common to both noses 101, 102.
More specifically, each nose comprises, respectively, a central pin 161, 162, non-deformable, extended externally by a collar 163, 164 elastically deformable. Each collar is shaped to have an application surface 165, 166 adapted to come into contact with the lens L1 and to conform to the shape of the latter under the effect of an axial clamping force. Such axial clamping force is applied jointly to the two noses, in opposition, either by the jaws 95, 96 of the third transfer member 7, as illustrated in particular by FIG. 28, or by the shafts 613, 612 at the moment of their approximation for the final blocking of the lens on said shafts as illustrated by FIGS. 29 and 30. In the example, the application surface 165, 166 belongs for its peripheral part to said flange and for its part the most central to the pawn itself.
In addition, in the illustrated example, the application surface 165, 166 of each nose is covered with a thin lining 167, 168 of plastic material or elastomeric material. The thickness of this lining is of the order of 1 to 2 mm. This is for example a flexible PV or a neoprene.
As can be seen in FIG. 30, the application surfaces 165, 166 of the two noses 101, 102 do not have exactly the same shape. The nose 101, which is intended to cooperate with the front face of the ophthalmic lens, has a concave application surface 165 in the unconstrained state. The nose 102, which is intended to cooperate with the rear face of the ophthalmic lens, has a substantially planar application surface 166 in the unconstrained state.
We will see in detail in the following that the nose 101, 102 are transferred to the clipping means with the lens they grab and then realize without further repositioning of the lens blocking on the clipping means.
When anticipating a difficulty of trimming of the lens, because of its lens coating material or the special form of trimming envisaged, the blocking of the ophthalmic lens for its trimming can involve, in combination or In addition to the locking nose 101, a reference tassel 145. Such tassel 145 is visible in Figure 32 and has an adhesive application surface 147 for temporary attachment to the lens.
On the contrary, the application surface 165 of the nose 101 has no adhesive property, but an ability to frictionally cooperate with the lens for its immobilization.
For the cooperation of the reference glans 145 with the locking nose 101, the central portion of the pin 161 of the nose 101 is recessed and then has a stepped axial housing 144 opening on the application surface and arranged to receive the adhesive reference glans 145, as will be better explained later. The housing 144 opens at the center of the application surface 165 of the locking nose 101.
The reference tassel 145 is substantially smaller than the locking nose 101, so as to be suitable for all lens shapes and sizes. Thus, the application surface 165 of the blocking groove 101 has an area at least four times greater than that of the application surface 147 of the reference glans 145. Tests have made it possible to optimize the dimensions of the surfaces application of the glans and the nose. The application surface 165 of the locking nose 101 preferably has a surface area of 80 to 500 mm 2 and the application surface 147 of the reference gland has an application area of 20 to 80 mm 2. The locking nose has an outer diameter of between 10 and 25 mm and an inner diameter of between 5 and 10 mm and the reference tassel 145 has a diameter adapted to the inside diameter of the nose, i.e. between 5 and 10 mm.
For the rotational indexing of the nose 101 on the adhesive reference sheath 145, the stepped housing 144 has a cross section whose shape is not of revolution about the common axis AB. In the example shown, the section of the housing 144 is oval.
The centering adhesive tassel 145, better visible in Figure 32, has a stepped outer shape complementary to the housing 144, to be received in this housing without play, with a slight tightening. The common shape of the housing 144 and the glans 145 not being of revolution, as explained above, one thus obtains a rotational indexing of the glans 145 with respect to the nose 101.
The housing 144 is further arranged to receive the reference tassel 145 so that the application surface 147 of the reference tassel 145 is flush with the application surface 165 of the locking nose 101. In this case, the adhesive tassel 145 has an end shoulder 146 which limits its axial stroke in the housing 144 and which has an adhesive face 147 for sticking against the lens and which is flush for this purpose the application face 165 of the nose 101 when the shoulder 146 is in axial abutment against the corresponding shoulder of the staged housing 144.
As will be seen in the following description of the method of implementation, the reference adhesive tassel 145 can thus be placed in the housing 144 of the nose 101 to be optionally implanted with the nose 101 and in addition to the the latter on the lens to be centered and blocked in order to be trimmed. Thus implanted on the lens, the centering glue 145 embodies the centering reference determined by the measuring means 5, independently of any direct connection of the lens with the transfer means 2 and 7 of the device.
By proceeding in this manner, the centering referential of the lens is therefore materialized by the glued glue 145 which remains permanently implanted on the lens even when the latter has been discharged from the device to be mounted on the frame. It is thus possible to carry out one or more resumption of the lens, for the most delicate montages, without losing the reference centering of the lens, as is usually the case with adhesive locking accessories.
However, in accordance with the invention, this centering reference function is dissociated from the actual blocking function serving for the transmission of torque for immobilization in rotation of the lens on the shafts 612, 613 of the grinder. The torque transmission function is in all cases provided by the nose 101, 102 whose shape, dimensions and material are adapted to the cut-away lens. The adhesive centering glue 145 may therefore be unique, for all types of lenses and frames, with a size reduced so as not to interfere with the trimming of the lens when the contour thereof must be reduced to a minimum. reduced size, and secondly deposit the adhesive substance on as small a portion of the lens as possible to reduce the risk of scratching cleaning. Only the nose should be adapted to the work to be done, as will be better explained later.
The measuring means 5 are also designed to detect the presence or absence of the reference tassel 145 at a predetermined location.
The carousel of first and second transfers 2 is provided with reception means 140 of the reference acorn 145. In the present case, as is better visible in FIG. 32, the loading and unloading platform 30 is equipped on its upper face, next to each of the loading places 36 to 38, a vertical pin 140 for receiving an adhesive centering glue 145. Lights 142 are formed in the plate around each post 140. These lights, in this case three in number around each tenon, are in the form of disk portions of smaller diameter than the centering pin to be fitted on the pin 140 through a central bore (not visible in the figures) of the glans 145 .
When the operator has loaded an adhesive centering glue 145 simultaneously with the loading of a job on the plate 30, the measuring device 5 detects the obstruction of the lights 142 by said glans and informs the electronic processing and computer system 10C ).
The manipulator arm 7 is responsible for jointly implanting the locking nose 101 and the reference gland 145 on the lens. The electronic and computer system 100 communicates with said measuring means 5 when exercising their presence detection function and is thus informed of the presence or absence of a reference tassel 145 on the plate 30.
The electronic and computer system 100 is programmed to execute the following conditional instructions: if the presence of the reference glans 145 is detected, the manipulator arm 7 is controlled to implant the reference glans 145 on the lens with the locking nose 101; - Otherwise, the manipulator arm 7 is controlled by the system 100 to implant the blocking nose 101 alone.
The flange and the pin of each nose 101, 102 are made in one piece in the same material. Satisfactory results were obtained by squeezing the lens between the noses with a clamping force of between 400 and 1000 N and realizing the pin and flange in a plastic material such as PVC.
With regard to the thin lining allowing slip-free torque transmission, a plastic material or an elastomer having the highest coefficient of friction with the surface coating of the lens will be chosen.
Furthermore, as can be seen in particular in FIG. 30, the pin 162 of the nose 102 which is intended to come into contact with the concave rear face 9 of the lens L1, is articulated, by means of a cardan link 115, to a fixing portion 169. This attachment portion 169 is intended to be connected to the lower jaw 96 of the member 7 or the shaft 613 of the clipping means, the pin 162 then having a freedom of angular orientation around 115. This allows the pin 162 of the nose 102 to match the local angular orientation of the rear face 9 of the lens to allow the lens to be clamped against the other nose 101, the pin 161 of which is it is rigidly connected to the upper jaw 95 of the member 7 or the shaft 612 of the clipping means, without tilting angularly or transversely sliding the lens. This results in a gripping and a stable and precise locking of the lens along the boxing axis AB. The ball joint 115 is of the cardan type, that is to say that it realizes a transmission of torque around the axis of the nose 102.
As mentioned above, the noses 101, 102 exert a dual function. They are first used to achieve the gripping of the lens from its loading location on the plate 30 of the carousel of first and second transfers 2, when they present the lens in the intermediate position. Then, the lens being thus grasped, by means of the noses 101, 102, by the probing, gripping and third transfer arm 7 the latter operates the third transfer of the lens towards the shaping means 6. When the lens is taken supported by these clipping means (relay passage), the nose retains a holding role by tightening the lens and then exert a second function, derived from the first, which consists of blocking the lens in view of its machining in cooperation with the shafts and rotation drive of the shaping means 6. The nose then constitute drive stops forming an integral part of the clipping means 6. These different stages of the preparation process will be explained in more detail later.
This double function, gripping on the one hand and locking for clipping on the other hand, results in the presence on the nose 101, 102 of a double mechanical interface: - the transverse one (that is to say ie operating transversely to the axis of the nose which merges with the axis AB of tightening the nose) to cooperate with the removable fastening means by clip (clipping means) 97, 98 of the gripping jaws 95, 96 in order to achieve a temporary fixation of the noses 101, 102 on said jaws, the other axial (that is to say operating along the axis of the nose which merges with the axis of the shafts 612, 613 of the clipping means 6) for cooperating with the shafts 612, 613 of the trimming means to achieve a firm axial clamping of the lens sandwiched between the noses 101, 102 with a transmission without sliding of the rotation torque of the shafts to the lens.
Thus, in the example illustrated, for the removable attachment of each nose 101, 102 on the corresponding jaw 95, 96, the clipping rings 97, 98 cooperate with receiving notches 171, 172 arranged in correspondence on the noses 101, 102 transversely to the axis of the nose. Thus, when the noses are attached to the jaws 95, 96, their axis is parallel to the direction of translation of the jaws, which corresponds to the clamping direction. The two noses are thus turned toward each other, with their application surfaces 165, 166 facing one another, when they are attached clipped on the ends of the gripping jaws 95, 96. The two noses 101 and 102 can then be brought closer to one another or mutually apart to grip or release a lens.
For its mechanical interfacing with the shafts 612, 613 of the trimming means 6, each of the noses 101, 102 cooperates with the free end of the shaft 612, 613 corresponding by an interlocking system with complementary male and female parts providing, by form cooperation, a rotation drive without play. More specifically, in the example illustrated, each nose 101, 102 is provided with a housing 173, 174 which is not of revolution around the axis of the nose, but which presents on the contrary, for example, a conical form with an ovoid base. This housing is intended to receive without play a nozzle 620, 621 of complementary shape, formed at the free end of the shafts 612, 613 of the clipping means, so as to allow a torque transmission of the shafts 612, 613 to the noses 101, 102 and hence to the enclosed lens. In the example shown, the housing 173 of the nose 101 is formed on the back of the pin 161 opposite the application surface 165, while the housing 174 of the nose 102 is formed on the back of the attachment portion 169 to the opposite of the ball 115. Each nose is thus provided with means for locking it in rotation on the shafts 612, 613 of the clipping means. After their transfer onto the shafts of the clipping means, the nose then form stops for rotating the lenses.
As shown in FIG. 31, the assembly preparation device 1 according to the present invention also comprises a nose magazine 130 placed in the vicinity of the probing, gripping and transfer arm 7. This magazine storches the three pairs of nose so that these noses are easily grasped by the arm 7.
This store comprises for example three pairs 131 to 133 nose-like noses 101, 102 whose size is adapted to the size of the job of lenses to be cut and whose material is adapted to the surface treatment of the lens and in particular to the properties adhesion of it. More specifically, the diameter of the application surface 165, 166 of the nose is adapted to the diameter of the frame to optimize the transmitted torque and therefore the machining speed.
A set of several pairs of noses is arranged on the staggered store and the pair of adapted nose is automatically selected. In the example illustrated, the store 130 has three steps in steps. The upper stage home nose pair 131 for cutting lenses in a contour of small diameter; the intermediate stage home pair 132 for cut-off lenses in a contour of medium diameter and the lower stage home pair 133 for cutting lenses in a contour of larger diameter.
The three floors of the store 130 are provided with cradles 134, 135, 136 adapted to accommodate, in a vertical nesting movement, the corresponding pairs of noses 131, 132, 133. The two noses of a pair then rest in the cradle of the floor concerned along a common axis, abutting with their application surfaces against each other.
The arm 7 is controlled by the electronic and computer system to equip automatically, depending on the parameters of the lens job to be prepared, the pair of nose best suited. The removal of the appropriate nose pair by the arm 7 on the magazine 130 is carried out as follows. The jaws 95, 96 are in a horizontal common plane which also contains the common axis of the nose of the pair concerned. The clipping rings 97, 98 fitted to the end of the jaws 95, 96 have their opening facing the nose of the pair concerned. The wrist 81 of the arm 7 is then advanced horizontally towards the noses 101, 102 so that the clipping rings 97, 98 engage in the notches 171, 172, around the pin 161 and the fastening portion 169 of the noses 101, 102. The nose being thus clipped on the jaws 95, 96 of the arm 7, the wrist 81 of the arm 7 is lifted vertically so that the pair of noses 131, 132, 133 leave its home cradle 134, 135, 136. When the preparation of the lens is finished and the pair of nose used in that preparation can no longer be used for the preparation of the following lens, this pair of nose is redeposited on its cradle 134, 135, 136 associated with the store 130 in a reverse movement, with first a vertical lowering for interlocking the nose in the cradle, followed by a horizontal withdrawal movement of the wrist 81 of the arm 7 to force, against the elasticity own clipping ring 97, 98, the die engagement of the clipping of these rings with the nose.
In addition to the stepped positioning of the different pairs of noses in the store, a double mechanical coding makes it possible to avoid any discrimination error between the nose pairs.
A first mechanical coding means consists in the fact that the nose cradle 134, 135, 136 provided on each floor of the magazine 130 for each pair of noses has longitudinal and transverse dimensions specific to the pair of noses that it is intended to to welcome.
The second mechanical coding means consists, on the one hand, of transverse plug holes 120 formed in the pin 161 and the attachment portion 169 of the noses 101, 102, and on the other hand corresponding fingers or tenons, which are not visible. in the figures, equipping the jaws 95, 96 projecting transversely inside the clipping rings 97, 98, in the extension of the jaws 95, 96 to cooperate with the transverse insertion holes 120 of the noses 101, 102. When the two noses of the same pair are installed in the store, they are abutted coaxially and the holes 120 formed in each nose are spaced from those of the other nose of a certain spacing specific to the pair of nose considered, so that it is necessary for the electronic and computer system 100 to adjust accordingly, according to the chosen pair of nose, the spacing of the branches of the gripping arm. In the event of a spacing error, the coding fingers of the jaws 95, 96 of the arm will abut against the pin 161 and / or the attachment portion 169 of the noses 101, 102 and will not be able to penetrate into the transversal insertion holes of the pins. nose, then prohibiting the clipping of the rings 97, 98 around the nose in the notches 171, 172.
Alternatively, it could be expected that the spacing of the plug holes 120 of the nose stowed in their cradle of the store is the same for each nose, so that the jaws 95, 96 of the arm grip all of the nose with a constant spacing , whatever the pair of nose considered. In this case, the keying consists, after the nose has been gripped by the jaws of the arm, to measure the spacing or spacing of the plug holes 120 by tightening the two jaws to butt the nose against each other or to tighten the nose against a reference block of known thickness. This measurement then makes it possible to validate whether the pair nose input is that desired for the clipping of the job in preparation.
Electronic and computer control system The device 1 comprises an electronic and computer control system 100 consisting here of an electronic card designed to coordinate control of the measuring means, the clipping device, the means of reception and first and second transfers and the probing, gripping and third transfer means for automatically processing a lens, in accordance with the automated processing method to be discussed later.
The electronic and computer system 100 comprises for example conventionally a motherboard, a microprocessor, a random access memory and a permanent mass memory. The mass merger contains a program for executing the automated assembly preparation method according to the invention which will be described later. This mass memory is preferably rewritable and is advantageously removable to allow its rapid replacement or programming on a remote computer via a standard standard interface.
Capotaqe and access control As shown more particularly in Figure 2, the preparation preparation device 1 according to the present invention is enclosed in a cowling 20 which prevents inadvertent access to all the constituent parts of this device.
The cowling is in the form of a housing which has a front face 21 and an opposite rear face 22. The front face 21 is intended to be placed facing the operator and has an upper portion 23 and a lower portion 24 substantially vertical, these two parts 23 and 24 being separated by a substantially horizontal flat surface 25.
An access door 26 is articulated on this flat surface 25, between a horizontal closed position and a vertical open position as respectively shown in FIGS. 2 and 3. Only this access door 26 mounted articulated on the cowling 20 allows, in opening position, access to the means of reception and first transfer 2, as will be better explained later.
The device according to the present invention thus makes it possible to automate all the operations, avoiding any intervention by the operator, and thus to minimize the risks.
OPERATION (AUTOMATED PROCESSING METHOD) The editing preparation device which has just been described is implemented according to an automated method which will now be described.
According to a specific feature of the invention, it is proposed a treatment of lenses by job. The term "job", commonly used in the ophthalmic optics industry, covers a pair of associated lenses L1 and L2 belonging to the same pair of spectacles and therefore mounted on the same frame to equip a wearer.
The proposed device also makes it possible to process several jobs (typically two jobs) at least partly simultaneously, that is to say in masked time.
Automated processing of the preparation of a lob (first job Ji) Generically, the processing of a job breaks down according to the following steps.
Preliminary step Entering or transmitting the job input data As shown in Figure 38, in order to perform a correct optical assembly, in a preliminary step, the frame chosen by the wearer is placed on his nose and several measurements are made on the using a device called a pupillometer or any other morphological measuring or imaging device.
With this pupillometer, therefore, the operator collects several data among which: the interpupillary distance D which represents the distance separating the two pupils P1, P2, the interpupillary half-distances which represent the distances separating each pupil P1, P2 and the center 13 of the nose of the frame carried by the wearer.
The optician then raises, for example manually with a ruler or by imaging, the height H which represents the distance, taken vertically from each pupil P1, P2, separating the pupil P1, P2 and the lower edge of the circles C1, C2 of the frame worn by the wearer. This height can be measured either by means of presentation glasses having the frame chosen by the wearer and on the lenses of which the location of the wearer's pupils are marked with felt and then measured at the ruler, or by means of a system Digital image capture and processing of this image. This measurement therefore integrates information relating to the geometry of the chosen frame.
This information relating to the morphology of the carrier is then entered by the operator by means of an appropriate interface (typically a keyboard and a screen) and stored in a memory of the electronic and computer system 100.
On the other hand, information representative of the outline of the selected frame is also addressed to the electronic and computer system 100 which places them in memory. This information may for example be selected by the optician and then extracted from a database stored locally in the memory of the electronic and computer system 100 or on a remote server accessible via the Internet or a secure point-to-point link.
Finally, the optician or operator enters, in the memory of the electronic and computer system 100, the prescription parameters relating to the wearer for whom the job in preparation is intended. These are in particular cylindrical power axes and prismatic powers and axes, and possibly cylindrical power, spherical and possibly the addition of power.
Step 1.1 Presentation of the loading and unloading platform 30 in the loading position If necessary, the electronic and computer system 100 controls the rotation of the loading and unloading platform 30 to present two free loading places 36, 37 facing the door of the door. access 26.
Step 2.1 Opening the Access Door 26 Initially, the access door 26 is held closed. The rule is that the access door is generally closed to protect the internal organs of the machine and in particular the loading and unloading tray 30.
The opening of the access door of the device is performed at the request of the operator. At the request of the operator, the opening of this door is authorized by the electronic and computer system 100 restrictively during the loading and unloading steps, which will be exposed later.
Step 3.1 Loading lenses As can be seen in FIGS. 9 and 10, the loading and unloading platform 30 is rotated to occupy marked positions and in particular a loading position in which only two loading places 36 and 37 and two places unloading 41 and 42 are accessible to the operator after opening the access door 26. The third loading place 38 and the other two unloading places 43, 44 are hidden by the rest of the cowling 20. The operator so you can not go wrong by loading and unloading jobs on and off the board.
In this marked loading position, the clamps 46 and 47 corresponding to the loading places 36 and 37 are open and the two seats 34, 35 are in the high position. In this high position, the seats 34, 35 laterally mask the clamps 46, 47 and thus prohibit in combination with the cowling 20, on the one hand any inadvertent manipulation of these clamps by the operator, and on the other hand any intrusion of object inside the device, which could damage its moving internal components.
It is thus possible to load a first job of two lenses L1 and L2 on the respective bearing areas 72, 73 of the upper faces 70 of the seats 34 and 35. In practice, the two lenses L1 and L2 of the first job J1 are deposited. manually by the operator on the two places 36, 37 for loading the loading and unloading platform 30 accessible through the access door 26. This is the only physical intervention of the operator on the lenses. Of course, an automated loading of the lenses can be envisaged.
Step 4.1 Lowering the seats and pinching the lenses The two seats 34 and 35 are then controlled to move to their lower position in which the lenses L1 and L2 are located at the fingers 56 of the respective clips 46 and 47 (Figure 11). These clamps are then controlled in the closed position so that the flanges of the fingers 56 enclose the lenses L1 and L2.
When closing the clamps 46, 47, the jig 69 of each clamp moves inside the groove 71 of the corresponding seat 34, 35 during the closing and rotation of the clamps, so that the clamps 46 , 47 grip the slice of the lens over its entire thickness by overflowing on both sides of it.
The two lenses L1 and L2 of the first job J1 are thus pinched over the entire thickness of their wafer by the clamps 46, 47 of the loading and unloading platform 30. In particular, it is understood that the overflow of the clamps on both ends Another of the edge of the lens ensures a secure and firm grip of the lens (even when it has a low thickness.
The third clamp 48 corresponding to the third loading place 38 remained in the closed position (recalled by the elastic means 57).
Step 5.1 Lowering the seats 34, 35 of the lenses The lenses L1 and L2 being grasped by the clips, the lens seats are retracted further downwardly in the manner of a lift or elevator to avoid any friction during the operation. next step.
Step 6.1 First transfer of the first lens: rotation of the loading and unloading platform 30 for passage of the first lens L1 of the job J1 in the measuring device 5 The assembly of the plate 30 and the clamps 46 to 48 is driven simultaneously by rotating to bring the first lens L1 of the first job vis-à-vis the measuring device 5 (Figure 12). This rotation of the plate 30 is performed, seen from above, in the clockwise direction and under the control of the electronic and computer system 100.
In the aforementioned variant, during this rotational movement, the clamps are guided by the aliasing 69 of the fingers 56 which cooperates with the beads 75, 76.
Step 7.1 Reading of the first lens LI of the job J1 by the measuring device 5 The geometric and optical analysis of the lens L1 by the measuring device 5 is carried out automatically in accordance with the description that has been made previously to provide to the electronic and computer system 100 data mainly relating to the optical powers and the referential of registration of the lens (centering point and orientation). These optical power and tracking characteristics are stored by the electronic and computer system 100.
In particular, the acquisition of the locating characteristics indicated above will make it possible, in conjunction with the geomorphomorphological data acquired during the preliminary step described above, to determine the exact point of gripping and locking of the ophthalmic lens L1 on the carousel. reception means and first and second transfers 2 brought to the intermediate position (as explained below) and to determine the trimming parameters for controlling the trimming device 6 during the trimming.
The measuring device 5 also determines one or more local optical characteristics, in one or more remarkable points of the lens of interest for the characterization or verification of the lens or the job. This or these characteristics: are stored in a memory of the electronic and computer system 100. They will be later (see in particular step 9.1) reprocessed by the electronic and computer system to be combined with or corrected according to geometric data provided by the arm 7 in its probing function and relating to the spatial implantation of the lens in preparation on the plate 30, in a frame linked to the measuring device 5.
Step 8.1 Second transfer of the first lens: rotation of the loading and unloading platform 30 for probing the first lens L1 of job J1.
The plate 30 is actuated in rotation clockwise to place the lens L1 in a so-called intermediate position in which the lens is close to the arm 7 so as to be accessible to the arm for its probing on the one hand and for its gripping. on the other hand, as we will see in the following steps.
During this second transfer, the rotation of the plate 30 is controlled and followed by the control electronics in rotation of the plate 30 and is stored in a memory of the electronic and computer system 100. Conjointly, the position and the axis of the lens measured by the measuring device 5 during the previous step is followed and stored in memory.
Step 9.1 Scanning of the first lens L1 job J1 at the optical or reference center, and / or at any point of interest or remarkable (measuring point) of the lens.
FIG. 19 shows the probe, gripping and transfer arm 7 during probing of the lens L1 in order to determine the height or altitude e of the lens L1 with respect to the measuring device 5 by probing at one or several remarkable points of the lens in preparation to which it is desired to measure one or more optical characteristics such as optical powers (ie ophthalmic frontal). Such a remarkable point is for example the reference center CR (optical center for a unifocal lens and mounting cross for a progressive lens) on the concave face of the lens. More generally, this point may be any point of interest where it is desired to measure a local, spherical or cylindrical frontal optical power. This is typically, for example, the optical center of a unifocal lens or reference points for near vision and for the far mink of a progressive lens.
It is known that the spherical or cylindrical ophthalmic power is defined by the inverse of the distance between the focal point (s) and the concave rear face of the lens. The measuring device 5 makes it possible to measure the position of the foci or foci in the fixed reference system of the device. The probing of the concave face of the lens at the point of interest makes it possible to measure its position in this frame of reference and hence the distance or distances between the measured focus (s) and the rear face of the lens.
We proceed, more precisely, as follows.
The measuring means 5 have previously determined a local optical characteristic at one or more remarkable points of the lens of interest for the characterization or verification of the lens or the job. This characteristic has been stored in a memory of the electronic and computer system 100.
The arm 7, exerting its probing function, is controlled by the electronic and computer system 100 to determine the position, that is to say in this case simply the altitude, the point or points on one of the remarkable faces of the lens.
This position is stored in the computer and electronic processing system 100 to be combined with the value previously stored in step 7.1 of the local optical characteristic at the point considered. This combination is carried out by means of software comprising calculation instructions which, by combining the position of the remarkable point obtained by probing with the local characteristic of the lens determined by the optical measuring device 5, deduces therefrom the spherical powers and / or cylindrical of the lens at this remarkable point, for example spherical power at reference points for near vision and far vision. The spherical or cylindrical ophthalmic power is then calculated as being the inverse of the distance between the focal point (s) and the concave rear face of the lens.
In practice, two modes of operation are conceivable.
In a first mode, the measuring device 5 determines the position of a focus of the lens at said remarkable point or point of interest. The calculation instructions of the program executed by the system 100 then deduce the focal length of the lens at the remarkable point considered, from the approximation (or combination) of the position of the remarkable point obtained by probing with the position of the focus of the lens determined by the optical measurement made by the measuring device 5. The program then calculates the front optical power as being the inverse of this focal distance thus noted.
In a second mode, the measuring device 5 determines an approximate value of a power of the lens at a remarkable point of the lens. The calculation instructions of the program executed by the system 100 then correct the approximate power value of the lens obtained by optical measurement, as a function of the position of the remarkable point obtained by probing. This correction is made by the program by means of a mathematical correction formula resulting on the one hand from the approximation made during the optical measurement to evaluate the power at the point considered and on the other hand from the fact that the optical power is equal to the inverse of the focal length.
During this first probing, only the concave (lower) face 9 of the lens is palpated by the nose 93 of the lower branch 91. In a variant, it is of course possible to feel the convex upper face 8 of the lens L 1 means of the other nozzle 92 carried by the upper branch 90 of the probing means 85.
Step 10.1 Probing of the contour of the first lens L1 of the JI job The probe, gripping and third transfer arm 7 then probes the predicted contour of the lens after trimming in order to check whether this lens is of sufficient surface area and thickness to obtain the desired lens after trimming by the trimming device 6. The contour T is for example shown in Figure 20 while Figures 16 to 18 show the approach kinematics of the nozzles 92, 93 dies probing means 85.
The wrist 81 is first moved to bring the two nozzles near the periphery of the lens. In the illustrated example, the lower beak 93 (Figure 17) is first in contact with the rear surface 9 of the LI lens by translation of the branch 91 which carries the beak. Then, the upper beak 92 is moved by translation of the branch 90 to feel the front surface 8 of the lens (Figure 18). The assembly is then moved by the wrist 81 so that the beaks 92, 93 palpate the contour of the lens. This example is not, however, limiting and we can consider an inverse solution with contacting the upper nozzle first or a mixed solution with bringing and contacting the two nozzles simultaneously.
Step 11.1 Probing of several points in the vicinity of the boxing center of the first lens L1 job J1 and points for determining the normal to the boxing axis.
The boxing axis, previously defined for the implementation of the invention, is then determined (FIG. 21) by probing, with the nozzles 92, 93 successively in contact with the lens as in the previous step, of several points. (at least three points) located in the vicinity of the boxing center CB, in this case four points A, B, C, D. Step 12.1 First transfer of the second lens: rotation of the loading and unloading platform 30 for passage of the second lens L2 of the job J1 in the measuring device 5.
Step 13.1 Reading of the second lens L2 of the job JI by the measuring device 10 5.
Step 14.1 Second transfer of the second lens: rotation of the loading and unloading platform 30 for passage to the intermediate position for the purpose of probing the second lens L2 of the job J1.
Step 15.1 Probing of the second lens L2 of the job JI at the optical center.
Step 16.1 Probing of the contour of the second lens L2 of the job JI.
Step 17.1 Probing of several points in the vicinity of the boxing center of the second lens L2 of the JI job and points for determining the normal to the boxing axis.
Step 18.1 Confrontation of the characteristics of the first job J1 with respect to the input data.
The internal program of the electronic and computer system 100 proceeds to the validation examination, automatic or assisted, of the characteristics of the two lenses L1 and L2 of the job J1. This validation test consists of a double check, with: - an individual check of the conformity of the characteristics of each lens of the job with respect to the prescription entered by the operator in the memory of the electronic and computer system, and on the other hand, a control of the overall coherence of the characteristics of the two lenses considered as a job, that is to say according to their belonging to the same pair of glasses, with in particular the simulation of the mounting of the two lenses on the chosen mount and verification that this mounting is possible.
The characteristics for which each lens is individually validated are in particular: - type of lens: unifocal, progressive, double or triple focus, etc. spherical, prismatic, cylindrical powers, addition of power (s) for progressive lenses cylinder and prism axes, hue, index, material.
The characteristics for which the two lenses of the pair are considered jointly, in their belonging to the same job, are in particular: the centering of each lens on the frame according to the reference frame defined by means of the measuring device 5 for each lens and half pupillary distances and heights specific to the wearer, this centering making it possible to perform a simulation of the mounting of the lenses on the frame for which they are intended, as explained in more detail below, the expected axial position of the bevel or the groove on the edge of each lens relative to the front face of the lens, to ensure the aesthetics of the mounting (balanced axial positioning of the two lenses, relative to each other, on the frame) ; - the coherence of the hues, indices, degraded of the two lenses of the job, - the complementarity of the two lenses or membership of the two lenses to the same job: we check that the job consists of a right lens and a left lens and that these two lenses correspond to the same job.
In particular, the global reconciliation of the job marking characteristics is carried out as follows. On the basis of the information representative of the parameters specific to the wearer's morphology, in particular the pupillary half-distance and the height of the pupil relative to the axis of the horizontal, and information representative of the contour of the chosen frame, acquired during of the preliminary step previously described, the electronic and computer system 100 produces a video image which is displayed on the display screen such as an LCD screen (not shown). Therefore, on this screen, we will see in particular, on the same scale the outline of the frame and that of the uncut lens, with its particular characteristics, including the tracking points that are worn or those that have been determined by the implementation of the measuring device. Taking all these elements into account, measured, calculated or read, makes it possible to determine the position of the perimeter of the cut-away lens in relation to the initial ophthalmic lens and, as a result, the position of the point of gripping of the lens, with a view to trimming, which is usually the center of the rectangle in which fits the outline of a frame or "circle" of the mount.
The electronic and computer system 100 performs a computer processing of these geometrical-morphological data approximated with the data relating to the identifying characteristics of the ophthalmic lenses L1, L2 of the job J1, taken together, to simulate their mounting in the corresponding circles C1, C2 of the M mount chosen and possibly change their centering. FIGS. 39 and 40 show diagrammatically different steps of this joint centering of a pair of ophthalmic lenses of the same job in circles of a frame chosen by the wearer.
As illustrated in FIG. 39, each ophthalmic lens LI, L2 is positioned in each circle C1, C2 so as to make its optical or reference center CR coincide (mounting cross 11, FIG. 35, if the lens L1 is progressive). with the determined position of the pupil P1, P2 of the wearer relative to the circle C1, C2 of the frame M. When the initial diameter of the ophthalmic lenses L1, L2 is too small relative to the circles C1, C2 of the chosen frame M, one day is then created between the circle C1, C2 considered of the mount M and the edge B1, B2 of the lens L1, L2.
In a first step, the two ophthalmic lenses L1, L2 (here according to the arrow F) are then jointly (virtually) displaced while keeping the relative centering height H of the two ophthalmic lenses constant (the relative height being defined as the difference between the two lenses). centering heights H of the two ophthalmic lenses) as well as the interpupillary distance D separating the two optical or reference centers CR of the ophthalmic lenses L1, L2 as positioned in the previous step in order to eliminate the existing intersections between each circle C1, C2 of the frame M and the edge B1, B2 of each ophthalmic lens.
However, if, after such a (virtual) displacement of the two ophthalmic lenses LI, L2, there are still intersections between at least one circle C1, C2 of the frame M and the edge B1, B2 of the ophthalmic lens. Corresponding L1, L2, in a second step, either one of the two lenses or the two ophthalmic lenses L1, L2 are displaced, keeping the relative centering height H of the two ophthalmic lenses and slightly modifying the interpupillary distance. separating the two optical or reference centers of the ophthalmic lenses as positioned in the previous step in order to eliminate all the intersecting points existing between each circle of the frame and the edge of each ophthalmic lens.
In all cases, it is preferable, although not essential, that, during the (virtual) joint displacement of said ophthalmic lenses L1, L2, the relative centering height H of said lenses should be kept, so that once the ophthalmic lenses L1 have been L2 mounted in the circles C1, C2 of the chosen frame, the two optical or reference centers CR of the ophthalmic lenses L1, L2 and the pupils P1, P2 of the wearer are on the same level or horizontal line (see FIG. 40) even if they do not coincide.
As shown in Figure 40, the height H and interpupillary distance D being retained the wearer has only slightly shift his gaze to the left or right to get a good view to infinity.
At worst, if the interpupillary distance between the ophthalmic lenses to be mounted is not respected, the wearer will be forced to converge or diverge slightly when looking at infinity.
The electronic and computer system 100 displays the values of the prisms induced for each eye by a possible modification of the centering of each lens on the frame. It is then up to the optician to validate whether these values are acceptable or not and, therefore, to accept or refuse the refocused job. Optionally, the system 1 can automatically refuse the job or alert the optician via a graphical interface and / or sound in the case where at least one of these values exceeds a maximum threshold value. It can also be provided that the electronic and computer system 100 automatically accepts the job if the induced prism values are less than a predefined threshold value.
The electronic and computer system 100 further verifies that the near-vision zone 14 (FIG. 36) is located within the perimeter of the lens and allows the optician to visually check it by displaying this zone.
Finally, the electronic and computer system 100 compares by calculation and / or displays for comparison to judged by the optician the expected axial position of the bevel or the groove on the edge of one and the other of the two lenses. It is thus preferred the axial position of the two lenses on the frame, or in other words, the position of the rings or strapping son of the frame relative to the front faces of the lenses. This calculation or this visual comparison aims at aesthetically harmonizing this position of the rings or strapping son of the frame with respect to the front faces of the lenses so as to avoid a too pronounced asymmetry of the axial positioning of the left and right lenses relative to each other. to the other. If necessary, the axial position of the bevel or the groove of one and / or the other of the two lenses can be modified.
Alternatively, it may also happen that the mounting of the lenses L1, L2, or at least one of them, is not possible or desirable because of a mechanical impossibility or visual discomfort that this mounting would provide to the bearer.
Step 19.1 Accepting or Refusing the First JI Job The J1 job is accepted or rejected depending on whether or not the individual and global characteristics previously cited are validated and / or modified.
Alternative 1: If the first job J1 is refused (alternative 1), the following five steps are executed. Otherwise, they are ignored.
Step 20.1 Rotation of the loading and unloading tray 30 for presenting the first job JI next to the access door 26 (fifth transfer) Step 21.1 Opening the clamps of the loading and unloading tray 30 and raising the seats of the lenses by high position Step 22.1 Opening the access door to the operator's control Step 23.1 Taking the first job J1 by the operator Step 24.1 Loading the next job for processing, according to steps 3 and following Alternative 2: If the first J1 job is accepted (alternative 2 most likely), we ignore the previous five steps and we perform the following steps.
Step 25.1 Rotation of the loading and unloading tray 30 for presenting the first lens L1 of the job JI in an intermediate position for its gripping by the probing, gripping and third transfer arm 7 (end of second transfer) Step 26.1 Selection and clipping of the machining noses by the probing, gripping and third transfer arm 7 in the nose magazine 130 In practice, the two preceding steps are performed simultaneously in step 18.1 and / or 19.1 of confrontation and acceptance or refusal of the job. We work in masked time to save time, given that the first J1 job will be most often accepted.
Step 27.1 Taking the first lens L1 of the job J1 by the probing, gripping and third transfer arm 7.
After having performed the previously described probes, the probe, gripping and third transfer arm 7 sandwiches the lens L1 between the two noses 101 and 102.
A blocking axis AB (FIG. 14), called the boxing axis, has been defined previously as being the axis normal to the front face of the lens and passing through the boxing center CB. In order to avoid positioning errors, the upper nose 95 accosts the convex front face of the lens in translation along this boxing axis AB of the lens and remains pressed against the lens being wedged on this axis. The surface of the nose 101 is approaching the front face 8 of the lens by being already parallel to the tangent plane of this lens at the boxing center CB (FIG. 14). The docking then takes place with an overall and simultaneous contacting of all the points of the application surface 165 of the nose 101 with the face facing the lens, without tilting. There is thus no error of offset or angular tilting when docking this nose against the lens. Thanks to this precision, a subsequent recovery of the lens is possible since the risks of positioning errors are eliminated.
This docking kinematics and this blocking geometry are made possible by the many degrees of freedom of the wrist 81. As shown in FIGS. 22 to 24, the movement of the wrist 81 is adapted to approach the upper nose 101 first. The upper jaw 95 is fixed relative to the wrist, the nose 101 is approached by the movements in translation and rotation of the wrist 81.
Then, the screw 99 causes the translation of the lower jaw 96 (Figure 24) to approach the same way the second nose 102, along the boxing axis AB. As can be seen more clearly in FIG. 30, the ball-nose mounting 102 allows this nose, when docked against the rear face 9 of the lens, to match the local angular orientation of this rear face 9 of the nose. lens for allowing the locking of the lens against the other nose 101 which is rigidly connected to the upper jaw 95, without uncontrollably changing the position of the lens by tilting it angularly or sliding transversely.
The two noses are then precisely implanted on the lens which is firmly maintained. This results in a stable and precise locking of the lens along the boxing axis, without geometric error.
It will be observed that at this stage of gripping of the lens by the gripping means, the referential of the lens, which defines its centering and its orientation (or axis) and which has been measured by the measuring device 5, has been preserved. or followed by the electronic and computer system 100 during the second transfer of the lens by the plate 30 between the measurement position and the intermediate position. The nose, whose attachment geometry on the jaws 95, 96 of the arm is perfectly known by construction, are therefore implanted on the lens to seize it according to a geometry (positioning in the plane of the lens and orientation) known compared to the reference frame of the lens. The noses 101, 102 are thus implanted on the lens in an orientation and a position in the plane of the lens which may be arbitrary but which is in all cases perfectly known and stored in a memory of the electronic and computer system 100.
In this case, it is not intended to adjust, when tightening the nose 101, 102 on the lens, the relative angular orientation of the nose relative to the lens around the common blocking axis AB. This orientation, which is arbitrary, is memorized and materialized, at an angular offset known by the nose. This known angular offset is taken into account when trimming the lens.
It is however possible, for particularly difficult cases or to further improve the precision and safety of the placement of the nose, especially during a recovery of the lens for a grinding, to stick on the lens an adhesive centering glue 145 simultaneously tightening the nose on the lens.
When the operator has loaded an adhesive centering pen 145 simultaneously loading a job on the plate 30, the measuring device 5 detects the obstruction of the lights 142 by said glans and informs the electronic processing system and computer 100 .
In the absence of an acorn on the pin 140, the manipulator arm 7 is controlled by the system 100 to implant the locking nose 101 alone.
If the presence of the reference tassel 145 is detected, the manipulator arm 7 is controlled to implant the reference tassel 145 on the lens with the locking nose 101. The probe, gripping and third transfer member 7 is then piloted by the system 100 to come and seize this glans to implant on the front face 8 of the lens. More specifically, the probing, gripping and third transfer member 7 brings the nose 101 facing the glans on the plate and lowers the nose 101 so that the latter s'émmanche with a slight tightening on the glans, in favor the central housing 144 formed in the pin 161 of the nose 101. The glans is thus fitted tightly in the nose 101 and is conveyed therewith towards the lens to be grasped and locked. When tightening the noses 101, 102 by the branches 95, 96 of the member 7 on the lens, the adhesive face 147 of the glans comes into contact with the convex front face of the lens and adheres thereto. The glans 145 will then be implanted on the prepared ophthalmic lens until it is voluntarily removed by the operator, embodying the centering reference or tracking of the lens as measured by the measuring device 5 to allow one or more times of the lens.
By proceeding in this manner, the centering referential of the lens is embodied by the glued glue 145, as is usually the case. However, according to the invention, this centering function is dissociated from the actual blocking function serving for the transmission of torque for immobilization in rotation of the lens on the shafts 612, 613 of the grinder. This torque transmission function is in all cases provided by the nose 101, 102 whose shape, dimensions and material are adapted to the cut-away lens.
Step 28.1 Opening the gripper in charge of the first lens L1 of the job J1 on the plate Step 29.1 Third transfer of the first lens L1 of the job J1 for passing the relay from the carousel to the clipping means The lens L1 is then moved by the probe arm, gripping and third transfer 7 (Figure 5) to be removed from the loading and unloading tray 30. Then, this lens is transferred by this member 7 to the clipping device 6, as shown in Figures 26 and 27.
FIG. 28 illustrates the final phase of the transfer during which the lens L1 is at the same time maintained by the probing, gripping and third transfer arm 7, and by the shafts 613, 612 of the trimming means. state, the noses 101, 102 are held by transverse clipping by the upper jaws 95 and lower 96 of the wrist 81, and by axial locking by means of the trees 613, 612 along the boxing axis, the trees 613, 612 now sandwiched tightly. the two noses 101, 102 and, in the center, the lens to be cut.
The transverse shrinkage of the wrist is then controlled to disengage the jaws 95 and 96 from the noses 101, 102 so that the lens simply remains in engagement between the noses on the shaper (Fig. 29). During this transfer, there is no loss of reference since the noses remain permanently in the marked position and belong, as it were, to both the gripping arm and the clamping shafts and driving the device. clipping. Given the memorization of the repository of the lens previously performed, the electronic and computer system 100 deduces the position and orientation of this frame of the lens in the repository of the clipping device.
Figure 30 shows in longitudinal section the engagement of the two shafts 613, 612 with the two noses 101, 102 by interlocking.
Step 30.1 Probing of the first LI lens of job JI in the trimming device 6.
Before its machining and for the precision of the latter, the first lens L1 job J1 is palpated, while it is installed in the clipping device 6 being locked and driven in rotation between the shafts of the grinder, by the arm probing, gripping and third transfer 7. This probing is performed according to the desired contour and assumed (given the transfer of the lens without loss of reference) of the lens after trimming and according to the locating characteristics of the lens provided by the measuring device 5 and data of carrier morphology and mount geometry entered into memory.
This probing makes it possible to acquire in the memory of the electronic and computer system 100 with a great precision and in concreto the spatial configuration in the three dimensions of the lens locked between the shafts of the grinder, taking into account possible deformations of the lens. due to the tightening of the lens between the nose under the pressure of the trees. The electronic and computer system 100 then calculates by calculation the precise machining parameters: lens contour, three-dimensional shape of the bevel or groove, position and orientation of the pre-drilling holes.
Step 31.1 Machining (trimming) of the first lens L1 of the job J1 by the trimming device 6.
The electronic and computer system 100 drives the trimming device 6 to perform the machining of the periphery of the lens so as to cut the latter along the desired contour, taking into account the locating characteristics of the lens provided by the device. measurement 5 and carrier morphology data and mount geometry data entered into memory.
Depending on the type of editing the J1 job being processed is intended for (Circled Frame, Circleless Lens Mount, Nylon Strapping Mount), the lens is beveled, drilled, or grooved.
Step 32.1 Positioning of the loading and unloading platform 30 for depositing the first lens L1 of job J1 by the probing, gripping and third transfer arm 7.
The loading and unloading tray 30 is actuated in rotation so as to bring the unloading place opposite the trimming means 6, at a predetermined position at which the arm 7 will come to deposit the cut-away lens.
Step 33.1 Fourth transfer of the first lens L1 job J1 for return of the lens of the clipping means to the carousel.
After being trimming by the trimming device 6, the lens is again gripped by the probing, gripping and third transfer arm 7 to be deposited on an unloading place of one of the pairs of unloading places 41 to 44 ( Figure 33).
The lens L1 is taken up by the probing, gripping and third transfer arm 7 in the trimming device 6 to be deposited on the unloading place of the loading and unloading tray 30. This step is executed simultaneously with the preceding one for a work in masked time allowing a saving of time of treatment. Of course, the rotation of the loading and unloading platform for the proper positioning of the latter is completed before the deposition of the lens by the arm 7.
We understand here the interest of the particular arrangement of the loading and unloading platform with its three loading places and four unloading places.
Step 34.1 Depositing the first lens L1 job J1 in place of unloading on the carousel tray.
To proceed with the deposition of the cut-out lens L1 on one of the unloading impression 42 to 44, the arm 7 presents the lens horizontally and on the outside of the plate 30, slightly above the latter, such that so that the lower nose engaged with the lens is located radially facing the outer end of the tab 49 associated with the radial slot 45 of the unloading fingerprint concerned. The wrist 81 of the arm is then moved in a radial direction of the plate 30 so that the lower nose enters the plate 30 in favor of the radial slot 45 by pushing the tongue 49 in the retracted position against its spring.
When the nose axis reaches the center of the unloading fingerprint concerned, the arm descends to deposit the lens on the plate. Then, the lower jaw 96 of the arm 7 loosens to release the lens and the wrist 81 of the arm 7 retracts radially outwardly to disengage from the plate 30, leaving the tongue 49 to return to the outer light-covering position 45 .
Step 35.1 Rotation of the loading and unloading platform 30 for presenting the second lens L2 of the job J1 in the gripping zone by the probing, gripping and third transfer arm 7 (end of second transfer).
Step 36.1 Taking the second lens L2 job J1 by the probe arm, gripping and third transfer 7 along the boxing axis.
Step 37.1 Third transfer of the second lens L2 of the job J1 for the forward passage of the lens L2 from the carousel to the clipping means.
Step 38.1 Probing of the second lens L2 of the job J1 in the trimming device 6.
Step 39.1 Machining the second lens L2 job J1.
Step 40.1 Fourth transfer of the second lens L2 job JI for return of the lens L2 from the trimming means to the carousel.
Step 41.1 Deposit of the second lens L2 of the job J1 on the unloading place of the loading and unloading platform 30.
Step 42.1 Fifth transfer: rotation of the loading and unloading platform 30 for presentation of the first job J1 for unloading by the operator.
Step 43.1 Opening the access door 26 for unloading the first job J1.
The opening of the access door 26, to allow the operator to access the job JI prepared, is done at the request of the operator and under the control of the electronic and computer system 100 which allows the opening the door that the plate 30 is in the loading and unloading position.
Step 44.1 Unloading the first job J1 by the operator.
You can then load and process another job (third job J3). The cycle then resumes in step 4.
Processing of a second iob (iob J2) parallel to a first iob (iob JI) being processed In accordance with an advantageous aspect of the method, it is proposed to partially process, in masked time, two jobs (pairs of lenses associated with the same pair of glasses).
Figure 43 shows that the device 1 advantageously allows two jobs to be processed simultaneously. A second job can be loaded on the loading places 37, 38 while the first lens of the first job is in the trimming device 6 and the second lens of this first job is processed by the measuring device 5.
In this case, in fact, the processing of the first job JI proceeds as described above and the processing steps of the following job 2 are analogous. The processing of the second job J2 then consists of steps denoted 1.2 to 44.2 which are respectively similar to steps 1.1 to 44.1 for the processing of the first job J1.
However, it is intended according to the invention to treat the two jobs partially in parallel. In other words, some processing steps of job 2 take place simultaneously with other processing steps of job 1.
The processing of the second job can begin as soon as the relay pass is completed for the first lens L1 of the first job J1, from the loading and unloading platform to the clipping means 6, provided in step 29.1. A corresponding loading place of the loading and unloading platform 30 has in fact been released by the first lens L1 of the first job J1.
The processing of the second job J2 therefore takes place in parallel with the steps 30.1 and following of processing the first job J1.
More specifically, the steps going from step 1.2 of presentation of the loading and unloading platform 30 to the loading position in step 19.2 of acceptance or rejection of the job 2 are carried out parallel to the machining step 31.1. the lens L1 job J1.
The following steps going from step 25.2 for selecting the machining nose until the end of the processing of the job J2 are executed after the step 41.1 of depositing the second lens L2 of the job J1 on the platform unloading place. loading and unloading 30.
Priority Applications (1)
|Application Number||Priority Date||Filing Date||Title|
|FR0412850A FR2878974B1 (en)||2004-12-03||2004-12-03||Organ for handling and sticking an ophthalmic lens of goggles and device for automatically preparing the mounting of ophthalmic lenses comprising such a body|
Applications Claiming Priority (2)
|Application Number||Priority Date||Filing Date||Title|
|FR0412850A FR2878974B1 (en)||2004-12-03||2004-12-03||Organ for handling and sticking an ophthalmic lens of goggles and device for automatically preparing the mounting of ophthalmic lenses comprising such a body|
|PCT/FR2005/002885 WO2006061476A1 (en)||2004-12-03||2005-11-21||Element for manipulating and sensing an ophthalmic lens and device for automatic mounting preparation of an ophthalmic lens comprising said element|
|Publication Number||Publication Date|
|FR2878974A1 true FR2878974A1 (en)||2006-06-09|
|FR2878974B1 FR2878974B1 (en)||2007-02-16|
Family Applications (1)
|Application Number||Title||Priority Date||Filing Date|
|FR0412850A Expired - Fee Related FR2878974B1 (en)||2004-12-03||2004-12-03||Organ for handling and sticking an ophthalmic lens of goggles and device for automatically preparing the mounting of ophthalmic lenses comprising such a body|
Country Status (2)
|FR (1)||FR2878974B1 (en)|
|WO (1)||WO2006061476A1 (en)|
|Publication number||Priority date||Publication date||Assignee||Title|
|EP0679473A1 (en) *||1994-04-28||1995-11-02||Wernicke & Co. GmbH||Spectacles glass bevelling unit|
|US6283825B1 (en) *||1999-12-21||2001-09-04||Johnson & Johnson Vision Products, Inc.||Automatic trimmer machine|
|US6390887B1 (en) *||1999-12-21||2002-05-21||Johnson & Johnson Vision Products, Inc.||Pre-cutter and edger machine|
|FR2825308A1 (en) *||2001-06-05||2002-12-06||Essilor Int||Automatic or semi-automatic device for trimming ophthalmic glass|
Patent Citations (4)
|Publication number||Priority date||Publication date||Assignee||Title|
|EP0679473A1 (en) *||1994-04-28||1995-11-02||Wernicke & Co. GmbH||Spectacles glass bevelling unit|
|US6283825B1 (en) *||1999-12-21||2001-09-04||Johnson & Johnson Vision Products, Inc.||Automatic trimmer machine|
|US6390887B1 (en) *||1999-12-21||2002-05-21||Johnson & Johnson Vision Products, Inc.||Pre-cutter and edger machine|
|FR2825308A1 (en) *||2001-06-05||2002-12-06||Essilor Int||Automatic or semi-automatic device for trimming ophthalmic glass|
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|ST||Notification of lapse||
Effective date: 20110831