EP0090752B1 - Smoothing and polishing machine for optical lenses - Google Patents

Abstract

A machine is of the type comprising an oscillating movable head with a tool-holding spindle, driven in rotation above a lens-support. The lens-support is borne by a vertically movable spindle which is mounted inside a sleeve, flared out at its upper part to form two bearing surfaces and, the lens-support comprises a ledge which surrounds the part of the sleeve containing the bearing surfaces. The lens-support rests on a head mounted for free rotation in a fixed pivot so that when the spindle is moved upwardly, the lens-support is immobilized in a horizontal position, to deposit the lenses to be polished thereon, or to remove them after the polishing operation. When the spindle is moved downwardly, the lens-support, then at a distance from the bearing surfaces, can oscillate freely during the lens-polishing operation, under the effect of the movable oscillating head.

Description

The present invention relates to a smoothing and polishing machine for optical lenses.

The technical sector of the invention is that of machines and devices used for surfacing glass and more particularly optical glasses.

We know that the manufacture of optical lenses goes through several stages. The lenses are first roughed out, then they are "soft" and are finally polished.

We know roughing and smoothing machines operating automatically and requiring a minimum of manpower. There is also known a polishing machine with semi-automatic operation. Such a machine is described in document FR-A-2 332 841. It comprises a frame on which is mounted a polisher, a glass holder-housing, means for bringing the polishing glasses in contact with the polisher and for take the glasses back after being polished, which glass-holder-case is mounted to rotate freely on the frame. Said polisher is rotated by a motor carried by a movable head located above said glass holder housing, which movable head is driven by an oscillating movement.

This machine is specially designed to polish optical glasses semi-automatically.

The objective of the present invention is the development of a machine making it possible to "soften" or polish optical lenses semi-automatically by treating the lenses face after face, or automatically, the lenses being treated on both sides after passing through the machine.

This objective is achieved by the smoothing or polishing machine for optical lenses according to the invention comprising a frame on which is mounted at least one spindle intended to carry a softening or polishing tool, at least one lens-support-housing, means for delivering a polishing agent between the tool and the housing, means for bringing the lenses into contact with the tool to be softened or polished, means for putting the lenses on the support housing and for removing the lenses after they have been smoothed or polished, the lens-support-housing is mounted for free rotation on said frame, which comprises an oscillating moving head on which the tool-holder spindle is rotated above said lens-support-housing, characterized in that the slow-support-housing is carried by a vertically displaceable pin, which is mounted in a sheath, flared at its upper part, to form two spans extending horizontally e t in opposition on either side of the spindle and in that the casing comprises a skirt extending it downwards and comprising a flange extending towards the center of the casing to envelop the part of the sheath which comprises said spans, which housing is supported on a head mounted with free rotation on a fixed pivot located at the upper part of said spindle, so that when the spindle is moved upwards, the housing coming to bear on said bearing surfaces is immobilized in a position horizontal for depositing the lenses therein for surfacing or for removing them after they have been processed and when the spindle is moved downward, the housing, distant from said surfaces, can oscillate freely during surfacing of the lenses under the effect of the oscillating moving head.

The result of the invention is a machine for "softening" or polishing optical lenses comprising either a processing unit for surfacing the lenses semi-automatically, or comprising two units for surfacing the two faces of the lenses automatically .

The advantages of such a machine lie mainly in the fact that several units can be operated by a single operator.

• - la figure 1 est une vue de côté de la machine selon l'invention;
• - la figure 2 est une vue en coupe longitudinale de la tête oscillante;
• - la figure 3 est une vue en coupe partielle de la machine illustrant le montage du boîtier-support de lentille sur la broche qui le porte;
• - la figure 4 est une vue en coupe partielle de la partie inférieure de la tête oscillante illustrant plus particulièrement l'outil de doucissage ou de polissage et le dispositif d'éjection des lentilles après surfaçage;
• - la figure 5 est une vue en coupe illustrant, à plus grande échelle, le montage du boîtier-support de lentille;
• - la figure 6 est une vue en coupe du boîtier dont la surface d'appui des lentilles est concave avec une demi-vue de dessus du revêtement de ladite surface;
• - la figure 7 est une vue en coupe du boîtier dont la surface d'appui des lentilles est convexe, avec une demi-vue de dessus du revêtement de ladite surface;
• - la figure 8 est une vue en coupe d'un outil pour surfacer la partie convexe des lentilles;
• - la figure 9 est une vue en coupe d'un outil pour surfacer la partie concave des lentilles;
• - la figure 10 est une vue de dessus du fourreau dans lequel est montée la broche qui porte le boîtier-support de lentille;
• - la figure 11 est une vue de dessus schématique illustrant le dispositif de transfert d'une machine comportant une unité de sur façage pour doucir ou polier les lentilles sur une face;
• - la figure 12 est une vue de dessus schématique illustrant le dispositif de transfert d'une machine comportant deux unités de surfaçage pour doucir ou polir les lentilles sur les deux faces.

Other advantages and characteristics of the machine according to the invention will become apparent on reading the following description given by way of non-limiting example of the various parts and organs of the machine, with reference to the appended drawing in which:

• - Figure 1 is a side view of the machine according to the invention;
• - Figure 2 is a longitudinal sectional view of the oscillating head;
• - Figure 3 is a partial sectional view of the machine illustrating the mounting of the lens support housing on the spindle which carries it;
• - Figure 4 is a partial sectional view of the lower part of the oscillating head illustrating more particularly the smoothing or polishing tool and the lens ejection device after surfacing;
• - Figure 5 is a sectional view illustrating, on a larger scale, the mounting of the lens support housing;
• - Figure 6 is a sectional view of the housing, the contact surface of the lenses is concave with a half-view from above of the coating of said surface;
• - Figure 7 is a sectional view of the housing, the contact surface of the lenses is convex, with a half-view from above of the coating of said surface;
• - Figure 8 is a sectional view of a tool for surfacing the convex part of the lenses;
• - Figure 9 is a sectional view of a tool for surfacing the concave part of the lenses;
• - Figure 10 is a top view of the sheath in which is mounted the pin which carries the lens support housing;
• - Figure 11 is a schematic top view illustrating the transfer device of a machine having an over-face unit for softening or polishing the lenses on one side;
• - Figure 12 is a schematic top view illustrating the transfer device of a machine comprising two surfacing units to soften or polish the lenses on both sides.

Reference is first made to FIG. 1 of the drawing which schematically illustrates a machine according to the invention comprising, a frame 1 surrounded by a bodywork comprising doors 1a for accessing the organs of the machine.

The machine comprises, at its upper part, an oscillating tool-holder head 2 which is pivotally mounted about a horizontal axis 2a, which is located at the rear end of an arm 2b and carries at its end opposite to the axis 2a, a movable orientable head 3. This consists of a chassis 3a and is mounted articulated on the arm 2b around an axis 4. It has on one side a toothed sector 3a which cooperates with a screw end 5, carried by the arm 2b and controlled by means of an operating wheel 5a. The polishing or smoothing tool is located in a protective screen, constituted by a bellows sleeve 6, which completely surrounds the tool to avoid projections of the polishing agent.

The tool is rotated by an electric motor 7 and a transmission composed for example of V-belts. The eastern movable head 3 is illustrated on a larger scale in Figure 2 of the drawing. It consists of a support 3 ₁ which is mounted rotatably the spindle tool 3 ₂ around ball 3 bearings _{3/3 4.} The spindle 3 ₂ extends beyond the upper part of the support 3 ₁ and comprises, at its upper end, a grooved pulley 3 ₅ , which is wedged on the spindle by means of a key.

The orientable head 3 also comprises, at its upper part, a casing 3 ₆ which envelops the part 3 ₅ and that, not shown, which is wedged on the motor output shaft 7 and the V-belts.

The spindle has at its lower part the polishing or smoothing tool 8. This (Figures 8 and 9) is in the form of a cylindrical plate. FIG. 8 illustrates such a plate seen in diametrical section for surfacing the convex part of the lenses. Its lower part 8 ₁ coming into contact with the lenses is concave and of a generally spherical shape, which is covered by a coating of synthetic material, for example polyurethane. FIG. 9 illustrates the tool seen in diametral section for performing the surface treatment of the concave part of the lenses. The lower part of the tool 8 ₂ coming into contact with the lenses is convex and of a generally spherical shape and is covered, like the part 8 ₁ of FIG. 8, by a polyurethane coating.

The tool 8 has, at its central part, a bore forming shoulders 8b / 8c to allow its mounting to the lower part of the tool holder spindle 3 ₂ .

The spindle 3 ₂ is cylindrical and has, at its lower part, a part 3 ₂ of larger diameter adopting the shape of a plate and on which plate the tool 8 is supported. The plate has, in its center, a cylindrical centering boss 3 ₂ b, which penetrates into a cylindrical housing 8d, reserved for the upper part of the tool.

The spindle 3 ₂ is hollow at its central part and from its upper end to the plate 3 ₂ a and thus comprises a cylindrical chamber 3 ₂ C which opens at its upper end 3 ₂ d, which is coaxial with the spindle.

The chamber 3 _2C is extended in the axis of the spindle through the plate 3 ₂ a by a tapped hole 3 ₂ e into which the axis 9 for fixing the tool 8 on the spindle 3 ₂ is screwed. This axis is cylindrical and is threaded at its part 9a to cooperate with the internal thread 3 ₂ e and comprises at its lower end, a cylindrical head 9b of larger diameter. The axis 9 is hollow at its center and comprises, from its upper end to its lower end, a cylindrical duct 9c, extending up to the head 9b, a first cylindro-conical chamber 9d of larger diameter than said duct , and a second cylindrical-conical chamber 9d of larger diameter than said first chamber 9d. The axis 9 comprises, at its upper end, a cylindrical housing 9f, extending approximately over the half-length of the axis. This comprises, in its central part, a pusher 9 ₁ extending: from its lower part to its upper part which it exceeds. Said pusher 9 _i consists of a cylindrical rod ₁ to 9 extending in the lower part, by a first cylindrical prominence 9 _1b, the latter so extended by a second prominence 9i c.

The protrusions 9 ₁ c / 9 ₁ b and the rod 9 ₁ a are engaged respectively in the chambers 9e / 9d and in the conduit 9c. The part of the pusher which extends outside the axis, at its upper part, consists of the head of a screw 9 ₁ e, screwed into a tapped hole reserved in the center of the rod 9 ₁ a. A compression spring 9 ₁ f, disposed in the housing 9 f, surrounds the rod 9 ₁ a and extends from the head of the screw 9 ₁ to a shoulder 9 g on which the spring 9 ₁ f is supported.

Under the pressure of the spring 9 ₁ f and in the initial position of the pusher 9 ₁ , the cylindrical prominence 9 ₁ c is in abutment in its housing 9e. In this position, said prominence is flush with the lower part of the axis.

The protrusion 9 ₁ c has in its center a blind hole 9 ₁ g forming a hexagon socket so as to be able to maneuver the axis by means of a wrench and to screw or unscrew it in the spindle 3 ₂ during the positioning or removal of the tool 8. To do this, the pusher is linked in rotation to the axis 9 by means of a pin 9 ₁ h extending diametrically to the axis and fixed thereto by its ends, by being forced into reserved holes in the wall of chamber 9d, which pins crosses a diametrical, rectangular lumen with rounded edges 9 ₁ j, reserved in the prominence 9 ₁ b. The light 9 ₁ j is large enough to allow the erasure of the head of the screw 9le when a pressure is exerted on its top, which has the effect of causing the protrusion 9ic to come out of the pusher and therefore to separate the lens remained with tool 8 at the end of surfacing.

In order not to damage the face of the glass brought into contact with the pusher, the latter comprises a washer made of flexible synthetic material, for example made of polyurethane 9 ₁ K. As can be seen in FIG. 4, the pusher 9 ₁ is, in its initial rest position, slightly retracted with respect to the periphery 8 ₂ of the tool 8.

The pusher 9 ₁ is actuated by a rod 10, located in the cylindrical chamber 3 ₂ c and fixed to the movable rod 11a of a jack, for example pneumatic 11, mounted on the casing 3 _s of the movable head 3 coaxially with the rod 10 and pin 3 ₂ . The end 10a the rod 10 is near the head of the screw 9 ₁ e forming the upper part of the pusher 9 ₁ . The separation of the lenses and the tool 8 is obtained by the jack 11, which when put under pressure, acts by means of the rod 10, on the pusher 9 ₁ . The tool-holder oscillating head 2 is carried by a double-acting cylinder 12, articulated by its end 12a to the frame 1 of the machine and by its end 12b to the arm 2b of said head 2. The oscillation of head 2 is obtained by means of an eccentric 13 wedged on the outlet of a gear motor 14 and a set of connecting rods 15/16. The connecting rod 15 is articulated at the end 16a of the connecting rod 16, which is articulated at 2a to the arm 2b. The adjustment of the positioning of the head 2 and of the smoothing or polishing tool with respect to the lens support-housing 17 is obtained by means of a flywheel 18, wedged at the end of a threaded axis 19 , mounted on the frame 1 and acting on a support 20, pivotally mounted on the said frame about a horizontal axis 21 on which support 20 is fixed the gearmotor 14.

The lens-support housing 17 is carried by a pin 22, disposed in a cylindrical sheath 23, mounted to slide in a boss 1 b of the frame 1 and extending vertically so that the upper face of the housing 17, on which the lens is supported, is in a horizontal plane at the time of this operation.

The sheath 23 has, at its upper part, a cap 23a, attached by screwing, and comprising a cylindrical part 23b which surrounds with a slight play the upper part of the boss 1b, which cylindrical part is extended upwards by a conical part 23c , which is flared at its upper end to form two bearing surfaces 23d diametrically opposite and extending in a horizontal plane. These ranges 23d are shown in top view in Figure 10 of the drawing. They are delimited at their end by a circular line 23d _i of radius R and laterally by two parallel straight lines 23d ₂ of spacing e, symmetrical with respect to the longitudinal axis of the spindle 22. The latter is slidably mounted in the sheath 23, extends over the length of the latter and is fixed at its lower part to a jack, preferably pneumatic, with double effect 24. The sheath 23 is adjustable in height on the boss 1b in which it is mounted in a cylindrical conduit 1c coaxial with said boss and has a flat 23e, reserved on the side of its lower part on which rests a locking screw 25 comprising an operating lever 25a cooperating with a thread formed in the boss 1 and extending perpendicularly to the axis of the spindle 22 and the sleeve 23. The latter is extended, at its lower part, by a pinion 26, mounted in a housing 27 and meshing with an endless screw (not shown) mounted on a shaft 28 extending orthogonal ment to the pinion 26 and comprising, at its free end, an operating wheel 29. The spindle 22 is free in translation along its longitudinal axis in the sheath 23 and is linked in rotation to the latter. It comprises, on the side of its upper part, a rectangular diametrical lumen with rounded edges 22a, in which is disposed a pin 30 extending transversely and force-fitted into reserved holes in the wall of the sheath 23. The sheath is threaded at its lower periphery and cooperates with the internal thread 26a of the pinion 26. When the locking screw 25 is loosened, it is understood that by operating the flywheel 29 in one direction or the other, the displacement is caused in the vertical direction, towards the top or bottom of the sheath 23 and of the spindle 22. When the desired position has been reached, the assembly is immobilized by the locking screw 25.

Figures 6 and 7 illustrate the lens-holder-housing 17 in two embodiments. The housing of Figure 6 is intended to receive the convex part of the lens to be surfaced; the housing of Figure 7, the concave portion of said lens.

The housing 17 is in a generally cylindrical shape and the carrier surface 17 _{1/17 2} of the lens extends orthogonally to its longitudinal axis. The surface 17 ₁ of the housing of Figure 6 is concave of a generally spherical shape and has, at its periphery, a flange 17 ₁ a so that the lens can be held laterally during the surfacing operation. The surface 17 ₂ of the housing of Figure 7 is convex of a generally spherical shape and has at its periphery, a flange 17 ₂ has chamfered to laterally hold the lens during the surfacing operation.

The curved surfaces 17 _{1/17 2} are covered by a surface coating 17 _3, consisting of cork agglomerate and rubber, which comprises, for example coating of the perforations 17 ₃ a distributed along its periphery and a reserved perforation in its center 17 ₃ b. These perforations form, when the coating is fixed, for example by gluing, on said curved surfaces, blind holes containing air, which has the effect of avoiding the adhesion of the lenses during polishing in order to facilitate their removal at the end of the surfacing operation.

The case is extended downwards by an enveloping part constituted by a shaped skirt 17a generally cylindrical, having a conical portion 17b which joins the upper portion having the surface of platen 17 _{1/17 2.} Part 17a has a rim 17c extending towards the inside of the housing, which rim is in a plane perpendicular to the longitudinal axis of the housing and delimits a circular opening 17d and therefore is parallel to the upper part which has the surfaces d 'platen 17 _{1/17 2.}

The housing further includes, below the bearing surface 17 _{1/17 2} and coaxially thereto and to the opening 17d, a tapered seat 17, the generatrices of the wall converge at a point located beyond the surface of platen 17 _{1/17 2} and on the longitudinal axis of the housing. The bottom of this housing forms a bowl 17f of a more pronounced taper than that of its side wall.

Referring now to FIG. 5 of the drawing which illustrates the housing 17 represented in FIG. 6, carried by the pin 22, mounted in the sheath 23.

The pin 22 has, at its upper part, a head 31 mounted for free rotation, which head is conical and of the same conicity as the housing 17e of the housing in which it is engaged. It consists of two parts: a central part 31a a forming a sort of plate at its lower part and a conical part 31b which envelops said central part 31a, which part 31b is rotatably mounted on the part 31a on a ball bearing 32, fitted around the central part 31a and in a cylindrical housing 31 d of the conical part 31 b.

The central part 31 a, which is fixed, comprises a conical housing 31 a _i whose apex is directed towards the side of the upper part of the head 31, which apex is reserved in an attached wear part 33, made of carbide steel .

The head 31 is supported on a pivot 34, also made of carbide steel, which is in the form of a cylindrical axis whose free end is conical and of the same conicity as that of the housing 31a ₁ and of the part added 33. The pivot 34 is mounted on a cylindrical end piece 35 comprising a cylindrical and threaded coaxial extension, screwed into a tapped hole 22b, reserved for the center and the upper part of the spindle 22. A cup 36, of cylindro-conical shape and extending downwards, envelops the upper part of the sheath 23 which forms a cylindrical boss 23e at this point. The sheath comprises, at the level of the boss 23e, an annular housing 23f in which is disposed a lip seal 37, the lip of which rests around the spindle 22. The diameter of the circular opening 17d is less than the diameter (2 R) of the flared part forming the bearing surfaces 23d and greater than its width e. This provision is necessary to allow the establishment of the housing 17 on the head 31 and its removal.

To carry out these two operations, the spindle 22 is placed in the position shown in FIG. 5, the housing is placed in an inclined position, so that one of the bearing surfaces 23d is passed through the opening 17d. The housing is then placed in a substantially horizontal position and is moved to the side of the opposite staff to pass the latter through the opening 17d; simultaneously with these two operations, the head 31 is engaged in the conical housing 17th.

In the position of Figure 5, the housing is in position to perform the surfacing of the lenses. The rim 17c being distant from the two bearing surfaces 23d, it can oscillate around the pivot 34 while being driven in rotation around the bearing 32 under the effect of the oscillating tool-holder head 2, the tool 8 of which attacks the lens in a so-called "strip" position, that is to say on the side of the periphery of the lens.

To deposit the lens on the housing or remove it therefrom, and in order to immobilize the housing in a perfectly defined horizontal position, since these operations are carried out mechanically by arms which will be discussed later, the housing 17 is pushed to the side of the oscillating head 2, under the effect of the jack 24, which carries the pin 22 until the rim 17c of the housing comes to bear on the surfaces 23d of the sheath 23, as is illustrated in Figure 3 of the drawing. In this position, the portion of housing 17 _{1/17 2} which receives the lenses is fixed in a horizontal plane.

Referring now to Figure 11 of the drawing which schematically illustrates a machine comprising a lens surfacing unit.

• A - poste de traitement de surface,
• B - poste d'approvisionnement en lentilles,
• C - poste d'évacuation des lentilles usinées sur une face.

Such a machine consists of three stations:

• A - surface treatment station,
• B - lens supply station,
• C - lens removal station machined on one side.

Stations A and B / C are located on two orthogonal axes XX ₁ / YY ₁ which intersect at a point O. Station A is located in front of the operator and comprises the lens-support-housing 17 au- above which is the tool holder oscillating head 2. Station B and station C are on the same line YY ₁ . Station B is located to the right of station A, station C on the left.

The lens supply station B comprises a vertical loader 38 in the form of a hollow cylindrical body in which the lenses are stacked above a pusher.

The station C for evacuating the machined lenses consists of a conveyor 39, the carrying strand of the mat 39a moves in the direction of the arrow F.

The end 39b of the conveyor, station A and station B are located on a circumference 40 of radius Ri.

The machine also includes a set of two arms 41/42, pivotally mounted around an axis located at the point 0 of crossing lines XX ₁ / YY ₁ . The arms 41/42 are, in the same horizontal plane, and are connected to each other by a part 43. They each have a part 41a / 42a, which parts diverge from point O and a part 41 b / 42b which is parallel to the line XX ₁ , when the arms are in their initial rest position, as shown in FIG. 11. Each of the arms carries, at its free end, a suction cup 44/45. These suction cups are located at the intersection of the bisectors of the angles of the orthogonal lines XX ₁ / YY ₁ and of the circumference 40 on which the suction cups move. Thus, at rest, the suction cup 44 is located at the intersection 46 of the circumference 40 and the bisecting line 01 of the angle AOC, and the suction cup 45 is located at the intersection 47 of the bisecting line OJ of the AOB angle. Lines 01 / OJ form a right angle.

In each of the suction cups 44/45 there terminates a compressed air line 48 and a vacuum air line 49. These lines are fixed to the arms and are connected by hoses to a vacuum pump for the line 49 and to a compressor. of air for the pipe 48.

• Au démarrage:
  • la tête oscillante porte-outil 2 est dégagée du boîtier-support-de-lentille 17.
    • a) Les bras 41/42 pivotent de 45° dans le sens de la flèche F1, la ventouse 44 s'immobilise au-dessus du boîtier 17, la ventouse 45 au-dessus du chargeur tubulaire 38.
    • b) Translation des bras vers le bas, simultanément l'organe poussoir du chargeur 38 pousse la colonne pour mettre la lentille supérieure au contact de la ventouse 45 du bras 42.
    • c) La ventouse 45 aspire la lentille sous l'effet de la pompe à vide.
    • d) Translation des bras vers le haut, le bras 42 portant la lentille.
    • e) Pivotement des bras de 90° dans le sens de la flèche F2, la ventouse 45 s'immobilise au-dessus du boîtier 17.
    • f) Translation des bras vers le bas pour déposer le lentille sur le boîtier 17 avec jet d'air comprimé sur la lentille pour la plaquer sur le boîtier support de lentille 17 et translation des bras vers le haut.
    • g) Pivotement des bras de 45° pour immobiliser les ventouses 44/45 à leur position initiale au-dessus des points 46/47.
    • h) Descente de la tête oscillante porte-outil 2 sur la lentille portée par le boîtier 17 pour réaliser le surfaçage sur une face.

The operation of the unit shown in Figure 11 is as follows:

• While booting:
  • the tool-holder oscillating head 2 is released from the lens-support-housing 17.
    • a) The arms 41/42 pivot by 45 ° in the direction of the arrow F1, the suction cup 44 stops above the housing 17, the suction cup 45 above the tubular loader 38.
    • b) Translation of the arms downward, simultaneously the pusher member of the loader 38 pushes the column to bring the upper lens into contact with the suction cup 45 of the arm 42.
    • c) The suction cup 45 sucks the lens under the effect of the vacuum pump.
    • d) Translation of the arms upwards, the arm 42 carrying the lens.
    • e) Pivoting the arms 90 ° in the direction of arrow F2, the suction cup 45 comes to rest above the housing 17.
    • f) Translation of the arms downward to deposit the lens on the housing 17 with a jet of compressed air on the lens to press it onto the lens support housing 17 and translation of the arms upward.
    • g) Pivoting the arms by 45 ° to immobilize the suction cups 44/45 in their initial position above the points 46/47.
    • h) Lowering of the tool-holder oscillating head 2 on the lens carried by the housing 17 to perform surfacing on one face.

• b) Translation des bras vers le bas, la ventouse 44, portée par le bras 41, vient au contact de la lentille façonnée précédemment.
• c) La ventouse 44 aspire la lentille façonnée.
• d) Translation des bras vers le haut, le bras 41 portant la lentille.
• e) Pivotement des bras de 90° dans le sens de la flèche F₂, la ventouse 44 s'immobilise au-dessus de l'extrémité 39b du convoyeur 39.
• f) Translation des bras vers le bas, le bras 41 se rapproche du tapis du convoyeur, et jet d'air comprimé pour faire tomber la lentille sur le tapis 39a. Evacuation des lentilles dans le sens de la flèche Fvers un bac de stockage.
• g) Translation des bras vers le haut et pivotement des bras de 45° pour immobiliser les ventouses 44/45 à leur position initiale au-dessus des points 46/47; et le cycle se poursuit autant de fois qu'il y a de lentilles dans le chargeur tubulaire 38.

During operations b to g, above carried out by arm 42:

• b) Translation of the arms downwards, the suction cup 44, carried by the arm 41, comes into contact with the previously shaped lens.
• c) The suction cup 44 sucks the shaped lens.
• d) Translation of the arms upwards, the arm 41 carrying the lens.
• e) Pivoting the arms 90 ° in the direction of the arrow F ₂ , the suction cup 44 stops above the end 39b of the conveyor 39.
• f) Translation of the arms downwards, the arm 41 approaches the conveyor belt, and a jet of compressed air to cause the lens to fall onto the belt 39a. Disposal of the lenses in the direction of the arrow F to a storage tank.
• g) Translation of the arms upwards and pivoting of the arms by 45 ° to immobilize the suction cups 44/45 in their initial position above the points 46/47; and the cycle continues as many times as there are lenses in the tubular magazine 38.

The lenses whose surfacing was done on one side are placed in a loader 38 to perform the surfacing of the other side not yet machined by performing the same operations as those which have just been described with reference to letters a to h.

FIG. 12 schematically represents a machine comprising two lens surface treatment units for machining the latter on the two faces.

The two units I / II are juxtaposed.

• A - Poste de traitement de surface,
• B - Poste d'approvisionnement des lentilles,
• C - Poste de transfert des lentilles usinées sur une face vers l'unité II.

Unit I has three posts A, B, C.

• A - Surface treatment station,
• B - Lens supply station,
• C - Transfer station for lenses machined on one side to unit II.

Stations A and B / C are located on two orthogonal axes XX ₁ / YY ₁ which intersect at a point O.

• A₁ ― Poste de traitement de surface,
• Bi - Poste relais des lentilles provenant de l'unité I,
• C₁ ― Poste d'évacuation des lentilles usinées sur les deux faces.

The unit also includes three stations A ₁ , B ₁ , C ₁ .

• A ₁ - Surface treatment station,
• Bi - Relay station for lenses from unit I,
• C ₁ - Station for removing lenses machined on both sides.

Stations A ₁ and B ₁ / C ₁ are located on two orthogonal axes ZZ ₁ / YY ₁ which intersect at a point O ₁ .

The stations B, C, B ₁ , C ₁ , are aligned on the axis YY ₁ .

Between the two units 1 is pivotally mounted, around an axis 50, a transfer device 51 also called a turning member and comprising a lens receiver 51a carried by an arm 51b. The pivot axis 50 is located on the axis YY ₁ in the middle of the distance between the stations B ₁ and C. The lens receiver 51 has described a circumference 52 for passing the lenses from station C to station B ₁ .

The arms 41/42 of the two units I are in the same horizontal plane and are identical and arranged in the same way as on the machine described with reference to FIG. 11 previously described. As on this machine, at station A of unit I, there is a box 17 surmounted by an oscillating tool-holder head 2; at station B there is a lens loader 38, identical to that which has been previously described.

Similarly and as on the machine of FIG. 11, at station A ₁ of Unit II, there is a housing 17 surmounted by an oscillating head carrying tool 2; at station Ci there is a conveyor 39 identical to that previously described.

The unit It comprises at station B ₁ a relay support 53, comprising a hollow circular receptacle 53a, covered with a surface coating of flexible synthetic material, for example polyurethane and in which receptacle, the lenses having just been treated on one side are deposited by the turning member 51. At the center of the receptacle 53a is reserved an orifice through which a jet of water is delivered to wash the face of the lens previously machined.

The turning member 51 pivots around the axis 50, under the effect of a double-acting cylinder (not shown), the movable rod of which carries a rack which meshes with a pinion wedged on said axis 50. During the pivoting 180 ° from member 51 of station C to station B ₁ (or vice versa) the arm 51b, which carries the lens receiver 51 a, rotates by 180 °, so that the lens deposited on the receiver 51 a at station C is returned and deposited on the relay support 53 of station B ₁ . Said receiver 51a is in the form of a circular-shaped casing with a diameter slightly greater than that of the lenses and the bottom of which is covered with a surface coating, for example made of polyurethane.

The rotation drive of the arm 51 b on itself during the 180 ° pivoting of the turning member is obtained by means of a bevel gear, one pinion of which is wedged at the end of the arm 51 b and the other in end of axis 50.

• Au démarrage, les têtes oscillantes 2 des unités 1 et Il sont dégagées des boîtiers-porte-lentilles 17.

The operation of the machine comprising two units is as follows:

• At start-up, the oscillating heads 2 of the units 1 and 11 are released from the lens-holder housings 17.

• a) Les bras 41/42 pivotent de 45° dans le sens de la flèche F₁, la ventouse 44 s'immobilise au-dessus du boîtier 17, la ventouse 45 au-dessus du chargeur tubulaire 38.
• b) Translation des bras vers le bas, simultanément l'organe poussoir du chargeur 38 pousse la colonne pour mettre la lentille supérieure au contact de la ventouse 45 du bras 42.
• c) La ventouse 45 aspire la lentille sous l'effet de la pompe à vide.
• d) Translation des bras vers le haut, le bras 42 portant la lentille.
• e) Pivotement des bras de 90° dans le sens de la flèche F₂, la ventouse 45 s'immobilise au-dessus du boîtier 17.
• f) Translation des bras vers le bas pour déposer la lentille sur le boîtier 17 avec jet d'air comprimé sur la lentille pour la plaquer sur le boîtier support de lentille 17 et translation des bras vers le haut.
• g) Pivotement des bras de 45° pour immobiliser les ventouses 44/45 à leur position initiale au-dessus des points 46/47.
• h) Descente de la tête oscillante porte-outil 2 sur la lentille portée par le boîtier 17 pour réaliser le surfaçage sur une face.

On unit I:

• a) The arms 41/42 pivot by 45 ° in the direction of the arrow F ₁ , the suction cup 44 stops above the housing 17, the suction cup 45 above the tubular loader 38.
• b) Translation of the arms downward, simultaneously the pusher member of the loader 38 pushes the column to bring the upper lens into contact with the suction cup 45 of the arm 42.
• c) The suction cup 45 sucks the lens under the effect of the vacuum pump.
• d) Translation of the arms upwards, the arm 42 carrying the lens.
• e) Pivoting the arms 90 ° in the direction of arrow F ₂ , the suction cup 45 comes to rest above the housing 17.
• f) Translation of the arms downward to deposit the lens on the housing 17 with jet of compressed air on the lens to press it onto the lens support housing 17 and translation of the arms upwards.
• g) Pivoting the arms by 45 ° to immobilize the suction cups 44/45 in their initial position above the points 46/47.
• h) Lowering of the tool-holder oscillating head 2 on the lens carried by the housing 17 to perform surfacing on one face.

• b) Translation vers le bas des bras, la ventouse 44, portée par le bras 41 vient au contact de la lentille façonnée précédemment.
• c) La ventouse 44 aspire la lentille façonnée.
• d) Translation des bras vers le haut, le bras 41 portant la lentille.
• e) Pivotement des bras de 90° dans le sens de la flèche F₂, la ventouse 44 s'immobilise au-dessus du récepteur de lentille 51 a.
• f) Translation des bras vers le bas, le bras 41 se rapproche du récepteur de lentille 51 a et jet d'air pour faire tomber la lentille dans le récepteur.
• g) Translation des bras vers le haut et pivotement de 45' pour immobiliser les ventouses 44/45 à leur position initiale au-dessus des points 46/47.

During operations b to g carried out by arm 42:

• b) Downward translation of the arms, the suction cup 44, carried by the arm 41 comes into contact with the previously shaped lens.
• c) The suction cup 44 sucks the shaped lens.
• d) Translation of the arms upwards, the arm 41 carrying the lens.
• e) Pivoting the arms 90 ° in the direction of the arrow F ₂ , the suction cup 44 comes to rest above the lens receiver 51 a.
• f) Translation of the arms downwards, the arm 41 approaches the lens receiver 51 a and an air jet to cause the lens to fall into the receiver.
• g) Translation of the arms upwards and pivoting of 45 'to immobilize the suction cups 44/45 in their initial position above the points 46/47.

• - Pivotement de 180° du bras de retournement 51 b pour mettre la lentille façonnée sur une face, dans la position de reprise, sur le support-relais 53, en vue du surfaçage de la deuxième face.

While the lens is facing at station A:

• - 180 ° pivoting of the turning arm 51b to put the shaped lens on one side, in the recovery position, on the relay support 53, for surfacing the second face.

• a) Les bras 41/42 pivotent de 45° dans le sens de la flèche F₁, la ventouse 44 s'immobilise au-dessus du boîtier 17, la ventouse 45 au-dessus du support relais 53.
• b) Translation des bras vers le bas.
• c) La ventouse 45 aspire la lentille sous l'effet de la pompe à vide.
• d) Translation des bras vers le haut, le bras 42 portant la lentille.
• e) Pivotement des bras de 90° dans le sens de la flèche F₂, la ventouse 45 s'immobilise au-dessus du boîtier 17.
• f) Translation des bras vers le bas pour déposer la lentille sur le boîtier 17 avec jet d'air comprimé sur la lentille pour la plaquer sur le boîtier-support-de-lentille 17 et translation des bras vers le haut.
• g) Pivotement des bras de 45° pour immobiliser les ventouses 44/45 à leur position initiale au-dessus des points 46/47.
• h) Descente de la tête oscillante porte-outil 2 sur la lentille portée par le boîtier 17 pour usiner la deuxième face de la lentille.

During operations a to h taking place on unit I, operations on unit II are as follows:

• a) The arms 41/42 pivot by 45 ° in the direction of the arrow F ₁ , the suction cup 44 comes to rest above the housing 17, the suction cup 45 above the relay support 53.
• b) Translation of the arms downwards.
• c) The suction cup 45 sucks the lens under the effect of the vacuum pump.
• d) Translation of the arms upwards, the arm 42 carrying the lens.
• e) Pivoting the arms 90 ° in the direction of arrow F ₂ , the suction cup 45 comes to rest above the housing 17.
• f) Translation of the arms downward to deposit the lens on the housing 17 with a jet of compressed air on the lens to press it onto the lens-support-housing 17 and translation of the arms upward.
• g) Pivoting the arms by 45 ° to immobilize the suction cups 44/45 in their initial position above the points 46/47.
• h) Lowering of the tool-holder oscillating head 2 on the lens carried by the housing 17 to machine the second face of the lens.

• b) Translation vers le bas des bras, la ventouse 44, portée par le bras 41, vient au contact de la lentille précédemment façonnée.
• c) La ventouse 44 aspire la lentille façonnée sur les deux faces.
• d) Translation des bras vers le haut, le bras 41 portant la lentille.
• e) Pivotement des bras de 90° dans le sens de la flèche F₂, la ventouse 44 s'immobilise au-dessus de l'extrémité 39b du convoyeur 39.
• f) Translation des bras vers le bas, le bras 41 se rapproche du tapis du convoyeur et jet d'air comprimé pour faire tomber la lentille sur le tapis 39a. Evacuation des lentilles traitées sur les deux faces dans le sens de la flèche F vers un bac de stockage.
• g) Translation des bras vers le haut et pivotement des bras de 45° pour immobiliser les ventouses 44/45 à leur position initiale au-dessus des points 46/47.

During operations b to g carried out by arm 42:

• b) Translation down the arms, the suction cup 44, carried by the arm 41, comes into contact with the previously shaped lens.
• c) The suction cup 44 sucks the shaped lens on both sides.
• d) Translation of the arms upwards, the arm 41 carrying the lens.
• e) Pivoting the arms 90 ° in the direction of the arrow F ₂ , the suction cup 44 stops above the end 39b of the conveyor 39.
• f) Translation of the arms downwards, the arm 41 approaches the conveyor belt and jet of compressed air to cause the lens to fall onto the carpet 39a. Evacuation of the lenses treated on both sides in the direction of arrow F to a storage tank.
• g) Translation of the arms upwards and pivoting of the arms by 45 ° to immobilize the suction cups 44/45 in their initial position above the points 46/47.

And the cycle continues in synchronism on units 1 and I1.

The surfacing operations taking place at station A, A ₁ and the transfer of the lenses by the turning member 51 and by the conveyor 39 occur at the same time.

Claims (12)

1. Fine-grinding or polishing machine for optical lenses comprising a frame (1) on which are mounted, at least one spindle (3₂), designed to carry a fine-grinding or polishing tool (8), at least a lens-supporting casing (17), means of delivering a polishing agent between the tool (8) and the casing (17), means of placing the lenses in contact with the fine-grinding or polishing tool (8), means of placing the lenses of the support casing (17) and removing the lenses after their polishing treatment, the lens-supporting casing (17) being mounted for free rotation on said frame (1) and said frame being equipped with an oscillating movable head (2) on which the tool-carrying spindle (3₂) is driven in rotation above said lens-supporting casing (17), machine characterized in that said lens-supporting casing (17) is carried by a spindle (22) which is vertically movable and mounted inside a sleeve (23) opening out at its upper part to form two bearing surfaces (23d) which extend horizontally and in opposite direction on either side of the spindle (22) and in that the casing (17) comprises a skirt (17a) extending from the base thereof and comprising a flanged edge (17c) extending towards the center of the casing in order to shield the part of the sleeve which contains the bearing surfaces (23d), said casing (17) resting over a head (31) mounted for free rotation on a fixed pivot means (34), situated at the upper part of the spindle (22), so that when the spindle (22) is moved upwardly, the casing (17) which can rest on said bearing surfaces (23d) is immobilized in a horizontal position in order to deposit the lenses thereon for subsequent surfacing, or to remove same after the surfacing treatment, and that when the spindle (22) is moved downwardly, the casing (17) which is apart from said bearing surfaces (23d), can oscillate freely throughout the lens-surfacing treatment under the action of the oscillating movable head (2).

2. Machine according to claim 1, characterized in that the head (31) has a truncated general shape, with generating lines converging to a point situated on its rotation axis and beyond its upper part, and is made up of two parts: a fixed central part (31 a) provided in its center with a conical housing (31 a₁) the apex of which is directed towards the upper part of the head, and on which apex rests the pivot means (34) and a part (31 b) shielding the said central part (31 a), which shielding part (31 b) is mounted for free rotation on said fixed part, on a ball or roller cage (32).

3. Machine according to anyone of claims 1 and 2, characterized in that the casing (17) comprises, in its center and on the side of its upper part, a conical housing (17e) of conicity similar to that of the head (31) so that the casing is centered on the head of the spindle (22).

4. Machine according to any one of claims 1 and 3, of which the casing (17) comprises, at its upper part, a flat surface or a concave or convex surface of general spherical form (17₁/17₂), on which surface is deposited the lens to be fine-ground or polished, characterized in that the said surface (17_1/17₂) is defined by a rim (17₁a/17₂a) to hold the lens during the surfacing operation, said surface being coated with a material constituted by an agglomeration of cork and rubber, said coating (17₃) comprising perforations (17₃a) to prevent any suction effect on the lenses and to help their removal at the end of the polishing or fine-grinding operation.

5. Machine according to any one of claims 1, 3 and 4, characterized in that the flanged edge (17c), situated at the lower end of the casing (17) defines a circular aperture (17d), said flanged edge being inside a plane perpendicular to the axis of rotation of the casing and being parallel to the upper part of the casing (17_1/17₂) which comprises said plane or concave or convex surface, of general spherical form.

6. Machine according to claim 1, of which the fine-grinding or polishing tool (8) is cylindrical and comprises a plane or concave or convex working face of general spherical form, characterized in that it is secured to the lower part and coaxially to the spindle (3₂) by means of a hollow axle (9), which is threaded externally to cooperate with a tapping (3₂a), provided in the spindle (3₂), inside which axle (9) is slidably mounted a push-member (9₁) which extends from the lower part of the tool to the upper part of the axle and there-beyond; said push-member is held in that position by means of a compression spring (9₁f) resting against a shoulder (9f) of axle (9), in that the tool-carrying spindle (3₂) is hollow through most of its length and comprises a pin (10) fixed to a jack (11) situated above the upper part of the spindle (3₂), the said pin (10) extending inside the spindle (3₂), in such a way that its lower end (10a) is situated, in its initial rest position, close to said push member (9₁) and in that, when the jack (11) is pressurized, the pin (10) which is brought to rest on the push-member (9₁) carries the latter in translation inside the hollow axle and causes the lower part of the push member (9₁ c) to emerge on the periphery of the tool (8) to push back the lens which is still applied against the outer face (8_1/8₂) of the tool.

7. Machine according to claim 6, of which the threaded axle (9) comprises, at its lower part, a cylindrical head (9b) which is brought to rest on a shoulder (8c₁) provided in the bottom of a cylindrical housing (8c) provided in the tool (8), characterized in that the push member (9₁) is composed of a pin (9_ia) provided at its lower end with a cylindrical protuberance (9₁c) moving inside a chamber (9e) provided in said cylindrical head (9b) of the threaded axle (9), which cylindrical protuberance (9_ic) comprises at its free end, a blind hole (9₁g) forming lateral faces for receiving a spanner, and between said blind hole (9₁g) and said pin (9₁a) a slot (9₁j) traversing through said protuberance, and in that the push member (9₁) is joined in rotation to said threaded pin (9) by means of a stop bolt (9₁h) integral with said axle (9) and extending through said slot (9ij) to allow the translatory displacement of the push member (9₁) with respect to the threaded axle (9).

8. Machine according to any one of claims 1 to 7, comprising a lens surface treatment unit, characterized in that the means used for bringing the lenses in contact with the fine-grinding or polishing tools (8) and for removing the lenses after the fine-grinding or polishing treatment consist of two arms (41/42) situated inside the same horizontal plane and mounted for rotating about the same vertical axis O, said arms comprising, at their free end, a suction means (44/45) into which opens a pressurized air pipe (48) and a depressurized air pipe (49), said suction means (44/45) moving over a circumference (40) on which is situated the surface treatment station A containing the lens-supporting casing (17) and the tool-carrying spindle (3₂) as well as a tubular carrier (38) inside which are stacked the lenses for grinding.

9. Machine according to claim 8, characterized in that the surface treatment station A and the tubular carrier (38) are situated on two orthogonal lines (xx1/yy1) intercrossing on the rotation axis 0 of said arms (41/42) and in that said suction means (44/45) are, in their initial rest position, situated on the bissectrices (Ol/OJ) of angles

formed by said orthogonal lines, so that when the arms (41/42) pivot in one direction or another, the suction means (44/45) move: in one direction (F_i), one above the lens supporting casing (17), and the other above the tubular carrier (38), or in the opposite direction (F₂): one above the lens supporting casing (17) and the other above one of the ends (39b) of a conveyor (39) in order to direct the lenses which have been shaped on one face towards a storage means.

10. Machine according to any one of claims 1 to 7, comprising two juxtaposed surface treatment units (1/11), characterized in that the means for placing the lenses in contact with the fine-grinding or polishing tools (8) and for removing the lenses after treatment, consists in two sets of two arms (41/42) situated inside the same horizontal plane, each set being mounted for rotation about a vertical axis (O/O₁) and said arms (41/42) comprising, at theirfree end, a suction means (44/45) into which opens a pressurized air pipe (48) and a depressurized air pipe (49) and the suction means (44/45) of each set of two arms (41/42) moving according to a circumference (40) on which is situated, on one of said units (I): a surface treatment station (A) consisting of a lens-supporting casing (17) and a tool-carrying spindle (3₂), a tubular carrier (38) inside which are stacked the lenses for grinding and a lens turning-over member (51) designed to place the lens in the surfacing position on a relay-support (53) of the second unit (II) and in that the suction means (44/45) of the other set of two arms (41/42) of the other unit (II) move according to a circumference (40) on which are situated: the said relay-support (53) on which the said lens turning-over member deposits the lenses in order to ground the second face, a surface-treatment station (Ai) comprising a lens-supporting casing (17) and a tool-carrying spindle (3₂), and one of the ends (39a) of a conveyor (39) for directing the lenses ground on the two faces, towards a storage means.

11. Machine according to claim 10, characterized in that the surface treatment station (A) and the tubular carrier (38) of one of said units (I) are situated on two orthogonal lines (XX₁/YY₁) intercrossing on the rotation axis (O) of one of the sets of two arms (41/42) of which the suction means (44/45) are, when in their initial rest position, situated on the bissectrices (Ol/OJ) of angles (AOC/AOB) formed by said orthogonal lines, so that when the arms (41/42) pivot in one direction or another, the suction means (44/45) move in one direction (F₁): one above the lens-supporting casing (17), the other above the tubular carrier (38) or in the opposite direction (F₂): one above the lens-supporting casing (17) and the other above the lens receiving member (51 a) of the turning over member (51) in order to deposit, on said receiving member (51 a), the lens which has just been ground on one face and in that the surface treatment station (A_i) and said relay-support (53) of the other unit (II) are situated on two orthogonal lines (ZZ₁/YY₁) intercrossing on the rotation axis (0₁) of the other set of two arms (41/42) of which the suction means (44/45) are, in their initial rest position, situated on the bissectrices (O₁I₁/O₁J₁) of angles (A₁O₁B₁/A₁O₁C₁) formed by said orthogonal lines, so that, when the arms (41/42) pivot in one direction or another, the suction means are placed in one direction (F₁): one above the lens-supporting casing (17), the other above the relay-support (53) or in the opposite direction (F₂): one above the lens-supporting casing (17), the other above one of the ends (39a) of a conveyor (39) to direct the lenses ground on both faces towards a storing means.

12. Machine according to any one of claims 10 and 11, characterized in that the lens turning over member (51) takes on the general shape of an arm comprising at its free end, said lens-receiving member (51a), said arm being mounted for pivoting about a vertical axis (50) and comprising means of pivoting same over 180° inside a horizontal plane and of causing it to pivot simultaneously about its own axis in order to turn the lens receiving member (51 a) over 180° and thus to deposit the lens on the relay-support (53) and place it in the position of surfacing of the non-polished face.

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