MXPA98002350A - Molding, expulsion and coating by immersion of thermoplastic lenses for anteo - Google Patents

Abstract

The present invention relates to an article of manufacture comprising: thermoplastic molded lenses; a cold channel attached to the lenses; the cold channel includes a stem with a free end portion, the free end portion includes a point above of the upper edge of the lens when the lenses are retained in the immersion position, the free end portion to provide a first position for a robotic fixture, the rod includes a second position along the length for a robotic fixture

Description

MOLDING, EXPULSION AND COATING BY IMMERSION OF THERMOPLASTIC LENSES FOR GOGGLES 1. TECHNICAL FIELD The field of the present invention is injection-compression molding of thermoplastic pairs of burr-free thermoplastic lenses, of improved cleaning, for glasses, to be fed into hard coating by in-line immersion. More specifically, a method and apparatus for multiple cavity injection molding of polycarbonate lenses for spectacles is integrated by complete automation with hard dip coating to produce clean, hard-coated molded lenses, made entirely within a single continuous housing of clean chamber air, which surrounds the lenses, without any human operator in it, which does not require any cutting or grinding of the lenses molded in pairs, neither of channel system before the hard coating, nor the use of CFC Freon (tm), or aqueous cleaning protocols before dip coating. An extension of this clean chamber housing and robotic handling can optionally provide automatic online inspection of the continuous product flow of optical energy, and the cosmetic quality of the lenses, and / or optionally provide thin film vacuum coating On-line anti-reflective of continuous product flow, before molded and hard-coated polycarbonate lenses come out of the continuous clean chamber air housing and / or receive manual handling. 2. Previous Technique A. Market Tendency of Rx to Polycarbonate Lenses The relevant field of the product are plastic spectacle lenses for ophthalmic prescription to correct vision (abbreviated hereinafter "Rx lenses") that have a refractive index greater than 1.530 glass and 1.49-1.50"CR-39" (chemically, cast-thermocracked lenses of alildiglicol carbonate, cross-linked with peroxide). This is the fastest growing category of Rx lens materials in the last five years, in markets both in the United States and around the world. These thermoplastic thermoplastics are injected and molded by injection are so desirable because the consumer / user of the lenses for glasses find them thinner (due to the higher bending energy in light of the plastic with high refractive index), and more light (lower specific gravity, particularly in the case of polycarbonate against CR-39). As a result, the myopic ("close-up") user of spectacle lenses can avoid the cosmetically undesirable appearance of "wearing bottle bottom lenses". In addition, the lighter weight means more comfort, less weight, less discomfort in the nose and in the upper part of the ears, where the surfaces that carry the weight are. Within this segment of plastic Rx lenses with higher refractive index, "thin and light", the statistics of the United States market shows a combined participation of 25-30 percent of the total market. However, within this segment, the participation of the high-index thermofix-emptying has remained essentially unchanged since 1991; almost all this growth in recent years is of the Rx type, thermoplastic, injection molded, more specifically incorporated by polycarbonate (R.I. = 1.586). (Although there are other candidate high-index thermoplastics that are also being considered, until now polycarbonate is more firmly established commercially - later on, "polycarbonate" will be taken to be inclusive of other optical-grade thermoplastic substitutes, such as it will be obvious to those skilled in the art). It is reported that the biggest reason for the market share shift towards polycarbonate Rx lenses, and far from the high-index, emptied-thermo-hardened Rx lenses, are the considerably lower manufacturing costs of polycarbonate Rx lenses at high production volume levels. This, in turn, is due to the high levels of automation that can be achieved with polycarbonate, but which can not be achieved inherently with the operations of emptying and thermofixing of more intense work. At a low volume percentage utilization, highly automated production can be weighed with an extremely high fixed cost, but as the volume increases the "critical point" levels passed, there is a crossing point where the inputs of Relatively higher variable cost of labor and materials, inherent to the cast-thermofixed casting become very inconvenient. After this, with the volume increasing, the incremental gain per unit of increased volume becomes highly tilted in favor of the more automated manufacturing operation (polycarbonate). This is reflected in the setting of market prices for lens manufacturers, where the high-index, emptied, hard coating Rx lenses are far from competitive in price with the corresponding prescriptions of coated polycarbonate Rx lenses. hard, injection-molded multi-cavities (especially, single-ended vision types ("FSV") that have higher unit sales volumes per Rx). Typically, high-index voided FSVs may have a higher price of 50-100 percent. It is for these reasons that another level of reduction in manufacturing cost, through an even higher level of automation, and through improved capital efficiency (= less critical point volume, which reduces the capital requirements for new manufacturing competitors within the field) will be strategically crucial in the future growth of polycarbonate Rx lenses.

B. Prior Art Patents on Multi-Cavity Lens Molding and Hard Dipping Coating Currently, the global production of polycarbonate Rx lenses is dominated by four companies, which together comprise an estimated share of more than 90 percent of the world market ( although there are new competitors just starting). Each of these four companies currently employs the same process form and multi-cavity injection-compression molding apparatus at the beginning of their "batch process" manufacturing flow diagram (see Figure 4A, Comparative Example). The next step is the cutting after the molding of the channel system and / or instantaneously desensitizing or roughing the ejector tabs, in such a way that the trimmed lenses can be mounted on a lens rack. Typically, these are semiautomatic operations aided by a human operator, but these can also be entirely manual operations. In Weber (U.S. Patent No. 4,443,159) there is shown an example of a molded hanger tongue that is adapted to engage a lens holder grille that carries a plurality of these lenses. The next step in the manufacturing flowchart is to use some form of cleaning protocol (all previous versions were Freon CFC ultrasonic steam degreaser methodologies; more recently, water-based cleaning is water spray at high pressure with centrifugal rotation, or multi-stage ultrasonic tank dives, followed by drying operations). Afterwards, these clean, dry lenses are coated by immersion in hard coating liquid solutions (either silicon heat cure types, or ultraviolet cure types), and the coating is cured by chemical crosslinking. Two of the four polycarbonate Rx lens manufacturers mentioned above are the licensees of the Applicants to the United States Patent Number 4,828,769 and of the United States Patent Number 4,900,242. A third party is the Gentex Corporation, attorney of Weymouth (United States Patent Number 4,933,119). A fourth is Neolens, attorney-in-fact of Bakalar (United States of America Patent Number 4,664,854). These patents employ some form of sequence of the injection-compression molding process, with a plurality of mold cavities, and employing different means to achieve cavity-to-cavity equilibrium therebetween. These three patents employed by four manufacturers differ in how the molded lenses are ejected from the lens mold, as can be easily seen by observing the edge and side wall of the O.D. of a few sample lenses from each manufacturer. Subsequently, more will be discussed about this in Figure 2 and its descriptive text. All three necessarily do at least some cut before the dip coating is possible. Seeing the other patents of the prior art showing the multi-cavity injection-compression molding of the Rx lenses, the Weber apparatus (U.S. Patent Number 4,008,031), for injection-compression molding of lenses Rx shows what appears to be a two-cavity mold. At 180 degrees opposite the entrance 23 of the gate is a hanger for use in subsequent dip coating operations. Weber also shows two molded 16 ejector tabs, located at approximately the clock positions of 10: 30-1: 00, with respect to the gate / drip mark location at 6:00 o'clock. Normally, this location would have the damaging effect of propagating coating flow runs along the front and back faces of the molded lenses, during the removal of the coating by immersion, but in the case of Weber, he has installed the hanging tongue and the ejector tabs on a circumferential flange 12, which is thrown back from the edges of the lenses both front and rear, such that then the overflow of the coating flow can follow this flange from top to bottom of each lens held individually (with the proviso that the lenses do not swing from side to side). Uehara et al. (U.S. Patent No. 5,093,049) also teaches and displays the injection-compression molding of the Rx lenses in a two-cavity mold, with the cavities connected by a cold channel and filling boss, with the filling protuberance being able to be mechanically interrupted at a predetermined time in the cycle, to avoid backflow. Uehara says nothing about any means of expulsion to unmold these two lenses, and no tongue or ejector spike is shown. If the forward travel of the mobile cores, which provides compression, is limited by hard stops, they can not be used to drive forward past the line of separation once the mold is opened, to assist in ejection. In that case, it will be up to a human operator to manually grab the cold fill boss and push to loosen the two lenses attached to it from the mold. No hanging tongue is shown or mentioned. Another historically important injection-compression molding of Rx lenses includes Spector et al. (U.S. Patent No. 4,836,960) and Laliberte (U.S. Patent Number 4,364,878), but both are limited to single-modalities cavity. Seeing now the prior art patents for immersion coating of Rx lenses (in addition to Weber (Patent of the United States of America Number 4,443,159)), Laliberte (Patent of the United States of North America Number 3,956,540, Method and Patent of the States United States of America Number 4,036,168, Apparatus) teaches a transfer form that is made portable from the lens holder grids through a multi-station machine, which internally has a clean chamber environment with filtered air, where the lenses are cleaned. and ultrasonically destatize successively, then coated by immersion, then dried and at least partially cured to a viscosity-free state, before the conveyor takes them to a loading / unloading station, where the operator can remove the glasses. Similar configurations were developed, using different automated transfer means, including two chain-drive conveyors operating in parallel, and connected by bars on which the lens-holder grids would be hung, or alternatively, an elevated conveyor with power and free flights could be used. for indexing, with removable suspended lens grilles mounted on it. These configurations for the Rx (and non-Rx) polycarbonate lenses typically use at least one (preferably two in series dives) Freon Ultrasonic cleaner / degreaser, where the polycarbonate lenses were immersed in the ultrasonic sump for a time prescribed, during which the formation of cavities (generation and collapse of microscopic bubbles) provides high kinetic energy working synergistically with the solvency of Freon (to reduce the adherent films that are carried on the dirt on the surface of the lenses), for This way throw away and carry away surface contaminants of both soluble and insoluble type. After remoof the lenses from the ultrasonic sump solution, a freon vapor / azeotropic alcohol zone will assist in rinsing and drying the lenses before going into the dip coating tank. Liebler et al. (UK Patent Application GB2 159 441 A, published December 4, 1985, attorney: Rohm GmbH) also teach the continuous production by immersion of scratch-resistant liquid coatings on plastic optical molds (such as lenses). It specifically teaches an endless conveyor belt for transferring lens grids containing a plurality of lenses. Among the optical plastic molds contemplated are the lenses for glasses, and Figure 2 shows a mold with an "ear 10 for fixing purposes, formed therein, and diametrically opposite to this ear end is a drip ear 11, in such a way that the excessive scratch-resistant coating composition can drip without forming a sharp edge when coated and dried. " (Lines 97-105). Compared to Laliberte, this machine is much simpler, merely contemplating a loading / unloading station, a liquid immersion coating station, and a drying station that is shown (described as. "Preferably, two or more infrared radiators). "It is not shown but it is mentioned in the text that ..." a cleaning bath can also be provided upstream of the immersion bath.The cleaning bath could be, for example, an ultrasonic bath containing an organic solvent " (Lines 122-128) However, it is believed that Liebler has never really been used for the coating of eyeglass lenses or for the coating of Rx lenses.There are major technical problems that Liebler did not anticipate. diametrically opposite hanger tab and drip tab would inevitably have coating flow runs propagated from the two joints of the coating tab, on their man unfortunately, these runs take place at the worst perimeter location, since the runs of the coating flow will go directly through the central, most critical area of the vision optics (see Comparative Example, Figure 2D). To the extent that Liebler's apparatus could be acceptable, it would not be believed to be for eyeglass lenses, but rather for ordinary immersion-coated lenses such as watch glasses, scales, and mirrors, none of which is required that has the high quality of image transmission that eyeglass lenses should have for vision correction. Where the hard coating is simply for heavy scratch protection, and the protective coated lenses are simply to provide some transparency to the product or device, these flow runs may be harmless and not be a functional problem. However, for eyeglass lenses for human vision problems that are the result of optical aberrations, these coating flow runs would be completely unacceptable, and the source of rejection imperfections by a very high percentage. If the tab configurations are as shown, of the total thickness of the lens mold, then the problem would be absolutely intrinsic. However, if the tab is not the full thickness of the lenses, as shown in Weber's drawings, but simply thick enough to support the relatively light weight of the lenses suspended by it, then that location of the lens would be acceptable. tongue, but only if the lenses are held level in assembly, not swinging back and forth, which would be another problem foreseen with Liebler's "auger conveyor".

C. Environmental and Economic Problems with Lens Cleaning Cleaning with "Freon" is based on the now unacceptable CFC-113 (decreases the ozone layer), whose production ceased theoretically on December 31, 1994, in accordance with the protocol of Montreal and its reviews EU. As a result, the new Rx lens installations necessarily have substitute aqueous cleaning approaches in place. One such approach uses high-pressure jets (up to 20,000 psi) of water spray that are swept across the front and back surfaces of the lenses, by moving the lenses (such as by turning them on an axle), or by means of moving the spray head (such as by reciprocal movement) or preferably, a combination of both. High pressure water spray is very effective in removing insoluble particulate forms of surface contamination (such as electrostatically maintained polycarbonate powder particles, or airborne inorganic powders), but has the inconvenience that this cleaning is 100 percent "observation line", so that not only should the lenses typically be cleaned one at a time, but a typical turn / spray combination requires that one side be cleaned and then, manually or by means of a robot, flipped and Replace on a different shaft to clean the second side. The performance of this equipment (number of lenses per hour) against the cost per job and the capital cost is much higher than the old Freon cleaners it replaced, which are now environmentally unacceptable. A second way of aqueous cleaning is to have a water-based ultrasonic detergent solution in the first stage of an automatic counter-current flow cleaning line, with multiple stations, with transportation that has been made transportable by taking the lenses through tanks. successive immersions (typically, at least five, and preferably 7-15 stations, including rinses with deionized water). Either by high-pressure water spray or by ultrasonic immersion in a multi-stage tank, the resultant clean but still wet polycarbonate lenses still can not be immersed into hard liquid coatings (which are all chemically incompatible with any percentage of significant water), in such a way that they have to face another problem, and that is how to completely remove all the remaining water from the lenses (and / or its lens rack), without creating surface stains ("water spots") on the optical surfaces of the lenses.

In the case of water immersion tanks, the last tank is typically kept at a very high temperature, close to the boiling point of the water (which can cause "fogging" due to a high percentage of humidity inside the clean chamber, where the coating must also be dried by immersion), and the removal speed of the lenses that are being removed from the tank is extremely low, to encourage the capillary effect to maximize water removal. In the case of rotation / high pressure spray, it is intended that the centrifugal action of the rotation speeds at high revolutions per minute throw all the excess water. However, because liquid hardcoat solutions can not withstand even small amounts of "entrained" water introduced by the lenses (even small droplets of water will result in marbling or staining of the coated lenses, or stained appearance) . In such a way that, inevitably, a hot air circulation dryer (filtering for cleaning) must be used, which makes an intensive and expensive energy operation. The online system water cleaner by automatic transfer of multiple stations, takes up a lot of space on the floor and is expensive (many $ 100,000). In addition, the disposal of the liquid effluent from these aqueous cleaning solutions is becoming an environmental problem that was not previously encountered with the Freon cleaners that replaced it. 3. OBJECTIVES OF THE INVENTION For these reasons, it is an object of the present invention to produce Rx lenses from multiple cavities that are demolished cleanly, are ready for dip coating, without cutting or grinding, or any use of Freon or aqueous cleaning protocols. , with a molded hanging tongue that has a special design suitable for handling and robotic transfers. Another object of the present invention is not to have any human operator touching the lenses, starting from the moment the multi-cavity demolding begins, until after the hard coating is at least partially cured to a viscosity-free state. Preferably, for minimal airborne contamination, there will not even be a human operator inside the same air space of the clean chamber, which surrounds the lens from the start of the demolding until after the hard coating is at least partially cured to a state free of viscosity. Another object of the present invention is to increase the productivity by means of changing the "transfer unit" being handled from the individual Rx lenses of the prior art to lenses Rx in pairs, molded together, leaving the mold ready to be handled robotically by means of the molded hanging tongue that has a special design. Another objective of the present invention is to minimize any plastic "flash" on the edges of the separation line of the lenses molded in pairs, in order to prevent the flow runs of the dip coating from propagating out of the flash and / or to eliminate any roughing of the burr before the dip coating, since these roughing processes generate contaminations of particles carried by the plastic air. Another objective of the present invention is to be able to demold the lenses cleanly, with expulsion processes that generate minimal (or none) contamination of particles carried by the metal or plastic air. Another object of the present invention is to further reduce the manufacturing costs of polycarbonate Rx lenses through improved performance percentages, fewer work in process inventories, and better labor productivity through this novel, fully automated flow chart of continuous process, against the flow diagram of the prior art of batch processes. 4. Description of the Invention The present invention employs principles of "design for manufacturability" that were found to be lacking in the prior art. An essential element of the present invention is that the transfer unit, from the demolding step to the coating and curing step, must be a pair of Rx lenses, not individual Rx lenses. Therefore, each time a robotic transfer takes place, the output is effectively duplicated in this way. This discernment is not found in the prior art, which teaches and shows only a single lens per tongue. A second element is to provide means for a flash-free molding process, by injection-compression, using forces with two-stage compensation spring, which determine the height of the cavity of the mold cavities of variable volume during filling, and the phases of expulsion of the cycle. (As used herein, "separation line burr" means the plastic thrown out of the set of molds, along the line of separation where side A and side B of the set of molds meet). Since it is not very likely that any "burr" of plastic will occur on the edges of the line of separation of the lenses molded in pairs, in the last fractions of a millimeter of the compression stroke "of closing the mold" during the process of filling, this element greatly increases the spring forces that keep the separation line of the mold set closed only during this last half millimeter of the compression stroke. The elimination of burr avoids the flow runs of the coating by immersion that propagate quickly out of the burr, and / or to eliminate any roughing of the burr before the dip coating, since the roughing processes will generate contaminations of particles carried by the plastic air. A third element is the novel demolding operations, which minimize or eliminate the generation of airborne particles that can contaminate the molded Rx lens product. This element is first incorporated into the design of the Rx lens product, more specifically, the detail geometry of the lens edge. Second, the considerations of the apparatus must be built into the mold design to provide the steps of the process required to automatically remove the Rx lenses molded in pairs, when the mold is completely open and a robot arm with suitable gripping jaws is in its proper location to receive the Rx lenses molded in ejected pairs (no manual assistance will be needed during the demoulding). A fourth element of the present invention is the removal of all the cutting and grinding of the solidified thermoplastic once the demolding has occurred, until after the coating has been applied by dipping and curing, at least to a viscosity-free state. The removal of the flash by improved molding processes (by the 2-stage spring force) is better than the deburring of the flash later. Any ejector tabs or drip tabs should be properly located along the perimeter of the lens, in order not to interfere with the proper dip coating, and not propagate flow runs of the coating. Specifically, none of these tabs will be placed in the upper 90 degree quadrant (defined as the 10: 30-1: 30 clock locations) of the perimeter of the lenses. The Rx lenses, which are cast in pairs, must be connected together by a cold channel, with the channel located in the side quadrant of the 1: 30-4: 30 clock for the left lenses, and in the lateral suadrant of the 7 : 30-10: 30 clock for the right lenses. A fifth element of the present invention is an integrally molded hanger tongue, typically located substantially equidistant between the two lenses in the molded pair, and substantially vertically wiping out the cold channel connecting the lenses in pairs (this symmetry has the advantage of minimizing side-to-side tilting of lenses in pairs). In an optional but preferred embodiment, the head of this molded casting tongue will be above the upper upper edge of the molded pair when held vertically, in order to prevent the hard coating by liquid immersion from contacting the robotic elements for The head will be gripped, so that the length of the rod between the head and the cold channel should be at least sufficiently above the upper edge of the lens. More preferably, the rod will be long enough, so that a second grip position with a sliding stop can be located also above the upper edge of the lenses in pairs. (In an alternative but less preferred alternative embodiment, the head of this molded hanger tab will be below the uppermost edge of the molded pair when it is held vertically, used with periodic cleaning of the hard coating by accumulated immersion which has been in contact with and has cured on the robotic elements to grab the head). Special features are designed inside the head in order to geometrically couple with certain robotic devices, fasteners of the work pieces, and grids. Optionally, a drip tab is located in the lower quadrant of each lens (positions 4: 30-7: 30 of the watch), to minimize the size of the drip mark of the coating by immersion, by means of a capillary wicking action, to drain the excess liquid coating once the lenses molded in pairs have been completely removed from the immersion in the bath by immersion. These optional drip tabs, however, would have the inconvenience of requiring a roughing operation after the coating is cured, and furthermore these will increase the use of polycarbonate resin + conste by lens. These four elements of the present invention allow the injection molding of multiple lens cavities for polycarbonate lenses to be integrated, by complete automation with hard coating by immersion, to produce lenses molded in clean, hard coated pairs, made entirely in of a single continuous clean chamber air housing, surrounding the lenses, without any human operator therein, without requiring any cutting or grinding of the molded lenses or channel system before hard coating, nor the use of Freon CFCs , nor aqueous cleaning protocols before dip coating. The novel combination of the processes and apparatus of the lens mold of the Applicants, and the design of molded lenses for manufacturing processes, contribute to this end. An extension of this clean chamber housing and robotic handling can optionally allow the automatic inspection of continuous product flow in line of the optical energy and the cosmetic quality of the lenses, and / or can optionally provide coating the antireflection thin film vacuum , continuous on-line product flow, before molded and hard-coated polycarbonate lenses exit the continuous clean chamber air housing, and / or receive manual handling. Another novel improvement using a special compensation spring assembly of 2 different types of springs has proven to reduce the burr of the separation line in variable volume injection-compression molding processes, which can be applied to any product. frosted molded plastic.

. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a mold for two-chamber Rx lenses of the present invention, in 2 divided cross-sectional views (showing different stages of the steps of forming and ejecting / unmolding the molded lenses, within a single molding cycle) and in a plan view. Figure 2 shows comparative examples of the prior art selected, paying special attention to the location of the drip mark and of the ejector tabs or gates that are needed for cutting before That the coating may be immersed, as well as the orientation of the hanging tongues. Figure 3 shows the lenses in pairs after ejection, with the preferred location of the hanging tab and the length of the stem, and the specific configurations of the head and the stem of the present invention, suitable for coupling with different variations of the position of the robotic grip, and the coupling geometries of the workpiece holder. Figure 4 shows manufacturing flow charts, showing the steps of the process in block diagram, and those steps that are to be performed robotically inside a clean chamber are shown inside boxes with dashed lines. 6. Ways of Carrying Out the Invention A. Lens Formation and Ejection Within the Mold Assembly The present invention employs a novel and convenient method and apparatus for ejecting multi-cavity molded Rx lenses by injection-compression, in molded pairs, each with a hanging tab (see Figure 3), while maintaining the cleanliness of both lenses in unmoulded pairs, and the optically polished molding surfaces of the set of molds, free of metal or plastic particles. Refer to Figures 1, IA and IB, which show a simplified two-chamber lens mold assembly, with the tip (not shown) of the nozzle of the injection molding machine, injecting into a sleeve (9) of cold filling extrusion, and a cold channel system (15), which is centered between the two cavities of the mold. An optional but preferred embodiment for molding two or more pairs of Rx lenses during a cycle of a single set of molds would rather use a hot runner system using a plurality of hot runner nozzle tips, rather than the only nozzle tip of injection molding machine, which injects into the sleeve (9) of the cold filling boss and the cold channel system (15); in U.S. Patent Nos. 4,828,769 and 4,900,242 of the Applicants (incorporated herein by reference), Figure 17, this hot channel apparatus is shown for a four-cavity mold. In U.S. Patent No. 4,965,028 to the Applicants, incorporated herein by reference, another alternative hot-channel system for optical thermoplastic molding is shown. It is convenient to construct a cold well (40) within the cold filling boss and the cold channel system, to trap "cold metal pieces" before they reach the lens mold cavities. Note that a slight recess (41) or negative angle of traction in the well (40) Cold will provide a positive mechanical retention force, which is useful later in the ejection steps. Another optional but preferred embodiment for forming pairs of Rx lenses within a single set of molds would employ "variable volume" mold cavities, wherein the height dimension of the initial cavity is larger before the injection begins than the dimension of thickness of molded end lens. This "variable volume" mold cavity mold assembly apparatus typically uses a sequence of injection-compression molding process to mold the Rx lenses, wherein a pulse force squeezes the molten substance injected at some point after the injection begins, to reduce the height dimension of this cavity (refer to the prior art lens molding patents to see different schemes for forces and impulse sequences). A preferred one, which is shown in U.S. Patent Nos. 4,828,769 and 4,900,242 of the Applicants, employs a resilient member 13 (such as a hydraulic cylinder or a mechanical spring) of Figure 10B, to determine the dimension of the height of the cavity, such that when the resilient member 13 is expanded or decompressed, the height dimension of the cavity is larger, by a length of compression travel length 40, and when the resilient member 13 contracts or compresses (such as by increased mold holding forces, exerted by the injection molding machine, squeezing the plates together, more preferably before the injection is finished), the cavity height dimension becomes more small by means of making the dimension of the compression stroke length 40 become zero. See Figures 2-8 that show this sequence of the injection-compression process throughout a complete molding cycle. The Applicants have found that since that patent was filed, that use of the hydraulic cylinders for the resilient member 13 inside the polycarbonate Rx lens molds is inconvenient, since the mold assemblies run at very hot temperatures (240-295). F; 120-150 ° C), causing the seals to leak and the oil to contaminate the forming surfaces of parts. The use of conventional coil-type die springs as the resilient member, does not have that problem, and they are long-lasting, and can give long compression stroke lengths (they have been used as high as 0.400"or 10 millimeters for molding very high negative energy Rx lenses, with a central lens thickness of 1.0-1.5 millimeters with a border thickness of 10-14 millimeters with a minimum "bond line".) However, these have burr problems during filling the mold, to eliminate the "burr" of the separation line, the spring force that holds the separation line together must exceed the force of the pressure of the fluid substance that is being exerted on the projected area moistened by the fused substance, and within the last 0.1-0.5 millimeters of compression travel is when burr formation can typically occur. "Burr" (plastic) must also be eliminated or minimized. which is poured out of the set of molds, along the separation line, where the side A and side B of the set of molds) of the separation line are joined, since otherwise it will be trimmed before the coating by immersion (thereby generating particles), or this can create runs of the coating flow by liquid immersion. The use of conventional high-deflection, very rigid coil-type die springs, such as the resilient member, to solve that problem creates a different problem during the ejection phase of the molding cycle, however, since so soon As the clamping force is released in preparation for the opening of the mold, these high spring forces act as a catapult for the lenses and the cold channel, by pushing prematurely towards the molding surfaces of the separation line, before that the ejection mechanism of the injection molding machine is activated. The present invention may preferably employ a novel combination of 2 different types of mold springs within the mold assembly, to give "2-stage" workings of these "resilient members". As shown in Figure 1 (shown in transverse split view, when the spring is decompressed, such as by releasing the mold clamping forces exerted by the injection molding machine, during the ejection phase of the cycle ), a conventional coil-type steel die spring (25) is used having long compression stroke lengths, but a moderate deflection force, in combination with an extremely rigid, very high deflection stack of sheaves (26) Belleville spring held in place by the shoulder bolt (29), to give 2 different levels of mold spring forces during 2 different phases of the stroke length - when any of the mold opening movements initial or final closing, are in the range of 0.0 to 0.5 millimeters, dominates the very high deflection force stack of Belleville spring rolls (26); thereafter, the weaker coil-type die spring (25) is the only applicable spring force, giving a mold-opening path that can be controlled (too high spring forces can then almost "catapult") the lenses molded in pairs outside the B side, maintained only by the retention (41)). Together, they determine the height dimension of the variable volume cavity, in each molding cycle to create a length of compression travel (21), up to a maximum dimension determined by the shoulder pin (29). In this optional but preferred embodiment of the present invention, this sequence of the injection-compression process is as shown in the Patents of the United States of America Numbers 4, 828,769 and 4,900,242 of the Applicants, Figures 2-6, but it differs after there (not as shown in Figures 7 and 8), in how the Rx lenses are to be demolded and ejected. For a flash-free injection-compression molding process, the use of forces with a 2-stage compression spring greatly increases the spring forces that hold the separation line of the mold assembly together, only during the latter half millimeter of compression travel. This process automatically changes the sum of the force of 2 springs, just when greater force is needed, in the last fractions of a millimeter of the compression stroke of "mold closing", during the process of filling the variable volume mold. The combination of 2 stages with the compensation spring of the Applicants (rigid spring applied only a short stroke + soft spring applied over the entire longer stroke) is an improved form of the "resilient member" operating within any of the injection molds- variable volume compression, in which the height of the cavity is determined by the degree of elongation of the springs. A review of the prior art cited herein and cited in U.S. Patent Nos. 4,828,769 and 4,900,242 of the Applicants, does not show any combination of 2 stages with compensation spring, nor any discernment on the benefit by the same . Specifically, any frosted plastic articles that are to be molded into a variable volume injection-compression mold, in which the height of the cavity is determined by the degree of elongation of the springs, will have the same tendency toward burr of separation line, and the larger the projected area of the cold channel system (especially if large fan gates or full length channel gates are used), the worse the problem of burr. If the article is flat and the length of the flow path of the molten substance is short, then a very short compression path length (from 0 to 1 millimeter) can be used, for which a single spring geometry is satisfactory. very stiff, in such a way that then the novel combination of 2 stages with compensation spring of the Applicants is unnecessary. However, if the article is non-planar in outline and the length of the flow path of the molten substance is longer, then a longer compression stroke length should be used (>; 1 mm; typically from 2 to 10 millimeters), for which a single very rigid spring geometry is unsatisfactory, then the novel combination of 2 stages with spring compensation of the Applicants is useful and necessary to control the tendency to burr formation. These other items may be other precision optical lens products (such as light-amplifying LCD lens arrays for flat-panel visual displays, many optically microstructured surfaces duplicated through molding, including "binary optics", "hybrid optics" ", fresnels and holographic image formation) and molded automotive windows, headlamp lenses, and mirrors, but also burglar-free, non-optical, opaque, burst-compression moldings of similar geometries, such as large body panels, are contemplated exterior for cars (chests, doors and fenders) and interior panels with textile surfaces in mold. It is known that all these non-eyeglass lens applications have considered or used variable volume injection-compression molding, and it is believed that the burr problem has deviated somewhat from its current use. Applicants have recently run these variable volume compression-compression molds with and without the combination of 2 stages with compensation spring, and these tests have clearly proven the claimed anti-burr benefit. The injection-compression molding process for reduced flash of the separation line in at least one molded thermoplastic article, operates within a set of molds mounted inside an injection molding machine that has programmable control of means for applying the forces of clamping which are applied, and the opening forces on a separation line formed between the A side and the B side of the mold set, and the injection molding machine has programmable control of means for moving forward or backward a ejector assembly inside side B of the mold set. The set of molds has at least one mold cavity of variable volume ground, having part forming surfaces in the insert of side A and the insert of side B opposed in pairs in front of the line of separation, and at least one member resilient passive resilient and compressible variable length determines a cavity height dimension of the mold cavity within previously established mechanical limits. The resilient member being an operative combination of: i) steel coil matrix spring to provide a moderate spring force over a very long distance, in a first clamping position of the mold set, with ii) spring steel sheaves , Belleville type, stacked, to provide a very stiff spring force over a very short distance in a second clamping position of the mold assembly, with the resilient member being mounted between the mold plate of the separation line of side B and the clamping plate on side B of the mold set, and exerting combined spring forces to bias forward the mold plate of the separating line on the B side, towards the separation line. In the process of injection-compression molding, when there is less clamping force exerted by the injection molding machine than a first spring force equal to the steel coil matrix spring force acting alone to bias forward the Mold plate of separation line of side B, towards the separation line, the length of the resilient member will be a maximum within the mechanical limits previously established in a first position of fastening the set of molds, and when there is more clamping force that the first spring force equal to the steel coil matrix spring force acting alone to bias forward towards the separation line, but less clamping force than a second spring force equal to the steel coil matrix spring acting together with the sheave force of the steel spring, to bias forward the separation line mold plate on the B side, towards the separation line, the length of the resilient member will be an intermediate value in a second clamping position of the mold assembly, and when there is more clamping force than the second spring force equal to the steel coil matrix spring acting together with the sheave force of the steel spring, to bias forward the separation line mold plate on the B side, towards the separation line, the length of the resilient member will be a minimum within the mechanical limits previously established in a third position of the set of molds. This process has the steps of: a.) Pre-enlarge the mold cavity by substantially closing a perimeter of the mold cavity in the separation line, in order to prevent bursting of the molten thermoplastic, in a first position of the mold set, formed by the application of a clamping force equal to a first spring force, such that a first cavity height equal to the sum of the desired compression stroke length plus a final thickness is determined of the molded item, before the injection starts; b.) Partially fill the cavity of the mold after the injection has begun, by progressively reducing the height of the cavity, in a second position of the set of molds, formed by increasing the clamping force applied to exceed the first spring force, but less than the second spring force; c.) Completely fill the mold cavity after the injection has finished, by progressively reducing the height of the cavity to reach a third position of the mold set, formed by increasing the clamping force applied to exceed the second spring force; d.) Cool the molded article within the mold cavity after the injection has been completed, by maintaining the height of the cavity substantially in the third position of the mold set, formed by means of maintaining the clamping force applied to exceed the second spring force, until a maximum cross section is below a glass transition temperature characteristic of the thermoplastic; e.) Expel the molded article by releasing the clamping force and opening the set of molds along the line of separation. In accordance with the present invention, once the optical grade thermoplastic has cooled to at least the glass transition temperature (for polycarbonate, this is equal to 296 ° F) even in the thickest cross-section, then the The resulting molded lenses must be stable in shape (the plastic molecules will have memory). Since molding productivity is improved by faster heat transfer rates between the molten substance in cooling and the mold inserts, it may be convenient to employ copper-based alloys, highly conductive, with a face of hard chrome or nickel, coated with metallic film by electrolysis, on the optically polished part forming surfaces, as building materials of the mold inserts. U.S. Patent No. 4,793,953 of the Applicants (incorporated herein by reference) is an example, for use in optical molding. Another improvement in the thermodynamics of optical molding is U.S. Patent No. 5,376,317 to the Applicants (incorporated herein by reference) employs the highly conductive, copper-based alloy mold inserts in a molding cycle that begins with surface temperatures of the mold insert over the glass transition temperature, then, after the mold cavity is filled and packed, the mold temperature drops well below normal hot temperatures (240-295 ° F) 120-150 ° C) that are used for the molding of Rx polycarbonate lenses. The first step of unmolding and ejection of the lenses in pairs begins with the release of the clamping forces applied by the injection molding machine, decompressing and extending by the same the resilient member comprising the combined springs described above. See Figure IB, the right-hand divided view, showing that the molded lenses (16) have already been separated from the optically polished part forming surface of the insert (14) of the B-side core, creating a space (17). ) of release between the concave surface of the lens and the convex surface of the insert on which it was formed. This release space (17) corresponds substantially to the dimension of the travel length (17) of. compression, when the spring of the set of molds is extended or decompressed by releasing the clamping forces of the mold exerted by the injection molding machine, during the same beginning of the phase of expulsion of the cycle. At the same time, the surface (19) of the extracted sleeve forming the edge of the lens, uses the thermal shrinkage of the molded lenses to assist in the separation of the surfaces of the perforation (sleeve 20) from the mold cavity. Very important, when zero traction is used in the perforation that forms the edge of the lenses, these lenses can be so strongly supported on the insert (14) of the mold of the B side by a partial vacuum, that the lenses are pulled back when the plate (28) of the mold on side B of the separation line with compensating spring comes forward (relative to the mold insert on side B). The Applicants have seen such examples, where the still hot hatches bend or, even worse, separate violently, leaving the lenses stuck on the insert of the B side in at the bottom of the perforation. By applying some positive traction to the B-side sleeve, a mechanical interference is created that prevents this possibility of the lenses being pulled back into the bore. See Figure IB. Note that the separation line (transverse plane CC) is not yet open at all, although the moving stage has traveled backward (compare the height of the set of molds measured between the holding plate (25) A and the plate (23) of subject B against the split view on the left, showing the condition completely fastened). With or without an optional air blow, when the separation line starts to open, the pairs of molded lenses are transferred out of side B, and pulled out of the optically polished part forming surfaces of the inserts (13) concave side A, since the cold filling boss (18) and the cold channel (15) of the pair-formed lenses are still firmly attached to the ejector mechanism (which is not yet activated), using retention (41) conventional mechanics (shown as a controlled traction angle in the cold well (40) of the filling boss) to "grab" the lenses (16) molded in pairs on the B side. (Also, deliberately running the temperatures of cooling on the B side cooler than those on the A side, may cause more shrinkage to occur on the B side of the molded lenses, thus reducing the retention forces on the A side of the lenses). See Figure 1. As the mold opening of the injection molding machine continues, after the maximum forward travel of the plate (28) of the B-side mold with compensating spring (set by the bolt (29) of the shoulder), then the separation line is opened. Once the sides A and B are no longer held together, separation forces are automatically applied, by this mold opening movement, which will exceed the partial vacuum that may exist between the convex surface of the molded lens and the surface of the insert of the corresponding concave mold, on which this was formed, since the lenses molded in pairs are still supported by mechanical retention forces (41) on the side B of the moving stage of the mold set. While these B-side retaining forces exceed the force that the lenses want to hold on the A-side inserts, without exceeding the cohesive force of the plastic in the cold channel and gate, pulling the lenses off of the A side will be mechanically positive when the separation line opens sufficiently during the opening of the mold. Then, as shown in Figure 1, the lenses (16) molded in pairs and the cold connecting channel system, including the mechanical retention (41), are removed from the B side by conventional ejectors (4), which are driven by movements of the cylinder (not shown) hydraulic ejector of the injection molding machine, connected to the ejector plates (24) of the set of molds, for which the ejector pins (4) are mechanically connected. The separation of the B-side lenses will also be mechanically positive. This step is only made when the mold set is completely open along the separation line, and the regulation of this ejector movement only starts after the arm end assembly of an extraction robot is in place to receive the lenses molded in pairs while they are separating from the mechanical retention. This regulation is coordinated between a programmable control of the injection molding machine and the extraction robot, with verification of the party to confirm that this distribution has been made. There are many brands and types of extraction robots for plastic injection molding machines. A type of side entry on the most common "up and out" rectilinear type is preferred, since the space above the mold platens is preferably where the HEPA filters will be located from the front to the bottom, and since a housing Clean chamber will be smaller and more compact if a side entry type is used. Typical manufacturers of side-entry extraction robots include Ranger Automation of Shrewsbury, MA, Conair Martin of Agawam, MA, and Automated Assemblies of Clinton, MA. Note that the ejection sequence mentioned above differs from the conventional manner in which plastic parts are ejected from injection molding, which begins first by separating the molded part away from the surface of the part forming cavity, when starting to open the mold, while holding the molded part on the surface of the part forming core. After the mold is completely open, then either a robot arm or a human operator is stretched in and pulls the molded part off the surface of the part forming core. In an optional but preferred embodiment of the present invention, filtered compressed air is used, in accordance with a prescribed sequence of "air blowing" steps, in order to provide a complementary driving force to separate the molded lenses from the surfaces of part formation, optically polished, to which these are subject by natural vacuum, due to thermal shrinkage, while closing the mold and maximizing the clamping force. Although the use of compressed air blowing to aid ejection is generally not new to those skilled in the art of injection molded thermoplastics, the Applicants are not aware of whether it has ever been employed in the injection molding of optical lenses. , and this is not found in any of the prior art patents relevant to this field. Refer to Figure IB. The Applicants use filtered compressed air (for cleaning the surfaces of the part-forming mold, as well as the surfaces of the molded lenses), introduced by the air line (10) of side A, and the line (11) of air from side B, within the intermediate open space (12) formed between the outer perimeter of each insert of the cavity (insert (13) of cavity of side A and insert (14) of core of side B) and perforation of the circumferentially surrounding sleeve (20). Valves (not shown) of air control the air flow and pressure inside the lines (10) and (11) of air, to provide air blowing in an ejection sequence, working in combination with spikes (4) ejectors conventional, which are driven by the movements of the cylinder (not shown) hydraulic ejector of the injection molding machine, connected inside the plates (24) ejectors of the set of molds, which are mechanically connected spikes (4) ) ejectors. In an optional but preferred embodiment of the present invention, even before the separation line is opened, filtered compressed air is fed through this intermediate open space (12) of "breathing gap" size passages (for the polycarbonate lenses, an intermediate open space of 0.001"(0.0254 millimeters) would not yet" form burr "), so that air forces begin to be applied on the B side (core side) of the moving stage, around of the perimeter of the convex insert, and to work inwards, towards the center of the lenses, to provide a clean separation outside the forming surfaces of part of the insert of the B side. At the same time, the surface (19) extracted from the edge of the lenses uses the thermal shrinkage of the molded lenses to assist in the separation of the lenses in pairs out of the stationary platen (side A) of the mold, before the line is opened of separation, in an optional but preferred embodiment of the present invention, a second air blowing step may be initiated, wherein equally filtered air enters around the perimeter of the mold insert of the concave, optically polished side A and urges the center of each lens to break the partial vacuum formed during molding. During this time, a substantial seal is still maintained by a seal overlap (42) of the small edge of the front of the lens over the perimeter of the lens mold cavity. See Figure IB. If this small seal overlap (42) is lost, the air blowing forces will be substantially weakened and may be ineffective, since the air will follow the path of least resistance and will bypass the center of the lenses, leaving some force of partial vacuum wishing to keep the molded lenses in place, during the next ejection step, which is the mechanical separation of the lenses off the surfaces of the concave insert by the clamping opening path of the molding machine, while they are being held firmly the lenses in pairs on the ejector that moves together with the side B of the set of molds.

B. For Cleaning, Never Cut Solidified Plastic Before Immersion Coating. Each immersion-coated polycarbonate lens is inherently ground, and hard coated by a glossy film that is easily seen to form a "drip mark" (which is the result of the gravity flow of the coating by liquid immersion on both surfaces). front as back). To examine these Rx lenses, let's look at a plan view of the hard-coated molded lenses, and find the location of the drip mark (which is easily seen as a build-up (37)) of the relatively thicker hard coating glossy film. , as seen in Figure 2B. When it extends as a clock face, we arbitrarily designate the location of the drip mark of any lenses as in the position at 6 o'clock. By examining this side wall of the lens edge, starting at the drip mark and passing circumferentially all around, one can see if some ejector tabs were used, and if so, whether the cut was before or after the coating by immersion, because if these tabs were cut before dip coating, they would show a shiny coating on the mark / residue of the cut, in addition to the grinding residue where the gate has been removed. Observing the sampled lenses of the current market, the Gentex and Neolens lens samples typically show one or more ejector tabs, most commonly 180 degrees opposite the gate. The Neolens sample showed four of these ejector tabs + the gate, all of which were cut before the immersion cleaning and coating operations (same as the Comparative Example of Figure 2). The reason why the tabs can not be tolerated in some locations on the edge of the lenses in the dip coating process is that the liquid coating in the upper half of the lenses would run downwards by gravity from the tip of the ejector tongue on the edge of the lenses, and this liquid coating stream will then flow vertically downward, from that location of the perimeter of the ejector tongue along the front or rear optical surface of the lenses. This "coating flow run" creates non-uniform light flexion (= aberrant image seen when looking through the thickest accumulated coating), causing a rejection of fabricated lenses. If one or more ejector tabs of molded polycarbonate lenses are to be cut before dip coating, this not only adds to the variable cost (more resin used per lens, more labor cost per operator handling, and roughing operations) ), but also directly reduces the surface cleaning of freshly molded lenses. There is no way to cleanly cut the solidified polycarbonate plastic without inevitably generating fine particles carried by the air ("polycarbonate powder"), which are immediately re-deposited on the front and back optical surfaces of polycarbonate lenses, because the electrostatic attraction forces will drag and fix them to the high dielectric constant polycarbonate surface layer. The use of ionizing air blowers can minimize this electrostatic attraction force, but actual tests of newly demolished lenses with field meters show 5-30 kilovolts of static charge, which only dissipates very slowly (in minutes, not seconds) due to the excellent electrical insulation properties of polycarbonate. Even if no ejector tongue is cut before coating, the lenses should be ground so that they can be hung by a molded flap over the lens rack (see Comparative Example in Figure 2), or if the cold channel of a molded pair of lenses is to be cut, so that they can be inserted by the molded flap tab into the lens rack (see Comparative Example of Figure 2A), then these grinding operations and / or channel cut, they will also generate fine polycarbonate dust as surface contaminants carried by the air. Apparently, manual handling by a human operator between the molding and dip coating steps is also required. After roughing and mounting on lens holders, these polycarbonate lenses are cleaned to remove any soluble surface contaminants (such as oil), and insoluble particulate debris (such as inorganic powders carried by the air, but more difficult, fine particles). of polycarbonate generated by the operations of roughing, and grinding and cutting of the channel). The lenses of the dealers of the Patents of the United States of North America Nos. 4,828,769 and 4,900,242 of the Applicants, do not use any ejector tongue, as can be verified by examining the edge of the lenses. However, if the shot injected (within a plurality of lenses connected by the cold channel melting substance delivery system) must be cut apart, in order to be mounted on the lens holder grids, then these operations of cutting channel have the same undesirable effect of generating polycarbonate powder. The statistically largest source of production loss percentage is the defective category known as "clear coating spots", where a transparent / translucent particle, of sufficient size and location to alter vision, is encapsulated within the bright film of the hard coating applied in liquid. Obviously, vigorous cleaning and a multi-stage dilution factor can make a difference in reducing this economic loss and production percentage. However, even with the best cleaners of today, remains the largest source of waste lenses. Refer to Figure 1A. The pair-molded lenses of the present invention will not have any hanging tongue (1) in the quadrant (6) of 90 degrees higher (between 10:30 and 1:30 o'clock), they will have gates (4) inside the quadrants (5) and (-5) right and / or left lateral (between 1:30 and 4:30 o'clock for (5), and between 7:30 and 10:30 o'clock for (-5) ), and if they use a drip tab (not shown) (optional), it will be located in the lower quadrant (7) (between 4:30 o'clock and 7:30 o'clock). See also the rod configurations (3) of hanging tongue and open spring head, described more in the examples with reference to Figure 3.

See now the Comparative Examples in the Figures 2, 2A, 2B and 2C. In contrast to the prior art cited, note that no ejector tongue is used on the perimeter of the Applicants' lenses (see Figure 3), and more specifically, in any location that required cutting before hard coating by immersion. The Comparative Example of Figure 2 shows a simplified 2-chamber lens mold with filling boss and cold channel (32). Note that each lens has a multiplicity of ejector tabs and the gate, each of which must be cut (33) in a separate operation after demolding, before dip coating, using the hanging tab (34) molded in the form of "T" The prior art patent that most resembles this Comparative Example of Figure 2 is that of Weber (U.S. Patent Number 4,008,031), differing only in that the Weber T-hanging tongue 20 is located directly opposite the gate 25, with an ejector tongue 16 on each side of the tongue 20. Weber needs to cut the feeding gate within the drip tab 23 before the coating can be made by immersion. Bakalar (US Pat. No. 4,644,854), cession to Neolens, shows in its Figures 4 and 5 the use of the ejector pin 15 opposite the gate, without showing any molded hanging tongue. In actual practice, the Neolens molded lenses have a plurality of ejector tabs and ejector pins that need to be cut before immersion coating, in an array just like the Comparative Example of Figure 2, thus needing 6 cuts (33). ) to prepare each lens for dip coating, using a tab (34) in an unknown manner in the location illustrated in Figure 3. Weymouth (US Pat.

North America Number 4,933,119), assignment to Gentex, does not show any ejector pin or ejector tongue, and does not teach any procedure to unmold or eject molded lenses. One should only assume that a human operator is employed to manually remove molded lenses, in which case high levels of airborne contamination over demolded lenses are inherent. All Gentex Rx lenses show at least 1 cut per lens before immersion coating (the cut is coated with glossy film). See now the Comparative Example of Figure 2A, which shows a simplified 4-chamber lens mold with filling boss 18 'and cold channel 35, feeding within 2 pairs of each lens, each having a gate 15 '. Even if the closest prior art (Patents of the United States of America Numbers 4,878,969 and 4,900,242 of the Applicants) were to be configured in 2 pairs as shown instead of 4 individual lenses, and even if a molded feature was added for grip and fixation, on the channel for each of the pairs, there would still be no way to dip-coating these lenses as they are demoulded, without at least 2 cuts (33) to separate the 4 cavities shot in the 2 pairs. There are additional limitations to the Patents of the United States of America Numbers 4,828,769 and 4,900,242 of the Requesters. See the ejection sequence in Figures 6, 7, and 8, where the resilient member 13 is held in its compressed or retracted position, so that when the ejector plate 17 is pushed forward by the injection molding machine, when the mold separation line is completely open, then the inserts 5b on the B side are pushed forward to pass the plane of the separation line, as shown in Figure 8, and the lens or molded optical disk is ejected. , as shown. Nevertheless, this Rx lens ejection method is NOT desirable for use with an in-line molding and dip coating process of the present invention. This reciprocating movement from the back to the front of the B-side insert, inside a tightly fitting hole, of at least many millimeters (lenses without height, single-ended view, can easily have a 10-millimeter border thickness) ) must inevitably lead to metal-to-metal wear and the resulting slag (which looks like scratched lines when the molded lens edge is seen); this is confirmed by visual examination of the molded lens edge of the Applicant's dealer using this "travel insert" injection method. The resultant metal-to-metal wear must generate contamination of very small metal particles that can be deposited in both the molded lenses and the forming surfaces of part of this optical mold, thus creating cosmetic rejections in immersion-coated lenses. Secondly, if severe scoring occurs, the irregular surface profile resulting from the perforation forming the side wall of the mold cavity then allows the molten plastic to flow into these small, scorched fissures, which are then cut off during the forces of ejection (as the traveling insert is pushed forward), thus creating a fine-particle plastic "powder" for more airborne contamination of the demoulded lenses and molding surfaces. For these reasons, it is found that the traveling insert method is not acceptable for the automated in-line immersion molding and coating of the present invention. Referring again to U.S. Patent Nos. 4,878,969 and 4,900,242 of the Applicants, note that Figure 9B shows drip tabs 99 in the 6 o'clock position of the molded lenses, but that even if there were a In the manner of separating the two molded pairs shown, without cutting after solidification of the plastic, the small cold well 31 is not located high enough to clear the edge of the lens, in order to serve as a grip tab or hanging for immersion coating, nor can the firm filling boss 19 be separated from the cold channel, without a cutting operation, which would generate contaminants of plastic powder. Refer now to the Comparative Example of the Figure 2C, showing a typical single lens of the prior art with the tab (34) in the position at 12:00 o'clock. If the immersion travel length of the dip coating is not extremely accurate, and the lens is immersed not only up to the top edge of the lens but beyond, partially above the tab stem, then the liquid will run back down of this rod by gravity, thus causing runs (38) of flow flowing back onto the optical faces of the lens. This is minimized but not entirely eliminated by reducing the thickness of the tongue, and pulling the tongue (34) back some distance from either face. Weber (Patent of the United States of North America Number 4,008,031) is an example. Refer now to the Comparative Example of the Figure 2D, showing an individual Liebler prior art lens (GB 2 159 441A) with a tab (34) of the full thickness of the lens, at the 12:00 o'clock position. Refer also to Figure 2 of Liebler, from which this lens is taken, which shows the lens F with an ear 10 and a drip tab 11. If the immersion travel length of the dip coating is not extremely accurate (which is impossible with the Liebler "auger conveyor" that immerses the lens), the lens will inevitably be partially submerged above the tongue stem, then the liquid it will run back down this rod by gravity, thus causing large flow runs (38) to flow back onto the optical faces of the lens.

C. Design of the Detail of the Edge of the Lenses for Clean Expulsion Refer again to Figure 1 of the Applicants, which shows a surface (19) extracted from the perforation of the mold cavity that forms the sidewall detail of the edge of the lens. In an optional but preferred embodiment of the present invention, this surface traction angle will be a positive value, when compared to the vertical ("zero traction"). This angle of traction should generally be increased in value directly proportionally as the thickness of the edge of the lenses increases. Also, note that adding a light molded edge at the junction of the convex surface and the side wall of the edge of the lens (typically, no more than 0.5 millimeter per side is sufficient), which acts as a seal (42) (see Figure IB), facilitates the blowing of compressed air which is optional, but preferred with the present invention. The models of molded or emptied Rx lenses are sold in nominal diameters, rounded to millimeters. Since all models of plastic eyeglass lenses, cast or molded, are subsequently cut at their perimeters in order to fit within a specs frame specific to the selection of the patient or the prescribing doctor, inherently all lenses Rx will "extend" to fit the eyeglass frame in which they are assembled. Because different fogging or imperfections can accumulate on the edge of emptied Rx lenses (such as bubbles or voids) and molded plastic lenses (such as residual bond line or gate opacity), or due to hard coating immersion (such as the "drip mark"), the practical method is to provide a surplus zone, consisting of a perimeter band 5 millimeters wide circumferentially around the edge of the lenses. Thus, in a lens model with a nominal diameter of 76 millimeters, for disposition purposes, only 66 millimeters internal would be considered useful, when 5 millimeters of surplus area per side were subtracted. The present invention utilizes the fact that the surplus zone exists for the purpose of altering the edge of the lens product and the details of the side wall for improved manufacturability. Refer again to Figures 1, IA, and IB. More specifically, in an optional but preferred embodiment of the present invention, the Applicants allow a plurality of interchangeable sleeves (20), each of which can be selected with its different surfaces. (19) removed, and assembled together with the convex insert (14) of appropriate assembly, for the purpose of molding each different lens magnification, in order to provide the cleanest possible release of the pair-molded, particle-free lenses. of metal or solid plastic that have been generated by the ejection process. Niel angle of extraction of the sleeve or the surface geometry can be optimal for the molding of all FSV Rx lenses, which should cover a wide range of product geometries. If a very steep extraction angle is used all the way down from the perforation and the surface of the sleeve that forms the side wall of the lens, there will be a sufficiently large intermediate gap between the sleeve and the insert, so as to "form burr ", which is unacceptable. Specifically, for molding a complete array of FSV lenses of positive and negative energy, it will require that the mold design accommodate widely differing lenses edge thicknesses. Positive energy magnifying lenses (for correcting hyperopia) will typically have a minimum lens edge thickness (2.0-0.8 millimeters). Conversely, negative energy de-magnification lenses (for myopia and short vision correction), they will have comparatively much thicker lens edge thicknesses (2.0-12.0 millimeters). It would be problematic to have a zero extraction angle on the edges of thicker lenses. However, because the assembly of the molding becomes much more complicated, the prior art patents do not show any provision for interchangeable or adjustable extraction angles. In current practice, the measurement of some commercially available Rx lenses that are believed to have been made by the cited prior art patents, shows a zero extraction angle and, therefore, confidence in a "brute force". to mechanically push out the lenses, despite the high holding forces in them. Doing this also increases the likelihood of generating both metal-to-metal wear, and shear stress of 1 metal to the plastic, both of which produce surface contamination of solid particles. As shown in Figures IA and IB, the present invention employs interchangeable mold sleeves (20) which become the part forming surfaces for the edge of the side wall of the lens. By means of exchanging a set of these sleeves having a certain surface (19) extracted previously determined, with another set having a surface / angle of extraction determined previously different, in order that they correspond with the inserts of the corresponding side B, for a desired specific negative energy FSV lens, one can controllably increase or decrease the angle of extraction of the molded lenses in resulting pairs for the entire range of FSV lenses as they are ejected, for the quality of molded lenses more clean. The thicker the edge of the lens, and correspondingly a higher negative energy, the greater the angle of extraction to be applied, but preferably only partially below the sleeve. For example, lenses with -2.00 diopters can have a shore thickness of 4.2 millimeters, and they would be released cleanly with an extracted edge of only 1.9 millimeters. Conversely, a FSV lens of -5.00 Diopter having a nominal shore thickness of 14.6 millimeters has a clean release by the use of an increased extracted edge of 7.2 millimeters.

D. Molded Tongue Designs Suitable for Robotic Handling in the Steps of the Immersion Coating Process After the lenses are formed in pairs having the aforementioned elements of the present invention, in injection molds-sompression of multiple sap of the present invention, and solidified therein, the demolding is carried out within a clean chamber housing which is preferably maintained at a positive pressure (ambient) from HEPA blower units. An extras robot is needed; preferably, of the lateral entry type, not the type of "up and out", such that the modular blowers that supply HEPA filtered air can be located directly above the platens, on the molding machine, to preferably maintain a positive air pressure inside the clean chamber housing substantially surrounding the mold (a deliberate intermediate open space located below the mold for an air leak, can improve the laminar flow pattern directed downward; likewise, a lower intermediate open spasm for directed air leakage is preferably located below the dip coating machinery). The side entry extractor robot operates inside a tunnel housed in a clean sámara, between the enclosed mold and an automated immersion coating machine, filtered by enclosed HEPA. When the mold is opened in the separation line, and the arm of the lateral input extractor robot is moved to its position, the pair of lenses is expelled forward into the gripping jaws of the end assembly of the arm mounted thereon. arm of the side entrance extras robot. In an optional but preferred embodiment, this robotic dip-back machine is its HEPA filter with positive pressure, filtered air in clean, self-contained chamber, it will be located between two injection molding machines and multi-sap molds, they are two robots of side entrance feeding pairs of lenses inside this robotic dip-coating machine. This "double line" system, in line, can be the most preferred modality in an individual molding machine and mold fed to a single re-surfacing machine, since typically the Rx lens molding systems are relatively long (1-5 minutes, depending on the magnification of the Rx lenses and the corresponding molding thickness). With longer lens lenses, the dual in-line sonfiguration is used in the molding step, for the output of insulated sapation per unit of the sapital equipment. See Figure 4B, which shows a block diagram flow diagram of the steps of the present invention, within a single clean samara housing (designated by the dashed line, showing all the steps that are performed within its perimeter of air spasm of clean sámara). This robotic device or dip-coating machine can take more modern forms. They are automated transport handled by conveyors by sanding (operating alone or in parallel, they are made by means of bars where the lens grids would be loosened) or, alternatively, a conveyor. high that can be graduated, or rocker conveyor. An optional but preferred embodiment employs a programmable SCARA cylindrical type robot, of the type manufactured by IBM, GMF Fanuc, and Seiko. This SCARA robot must have a suitably large working envelope (typically, up to 270 degrees of rotation, and at least 100 millimeters of Z axis), in order to be able to transfer these Rx lenses molded in pairs from a distribution point at some point inside the clean chamber housing of the coating machine, to at least one hard coating immersion tank, where a programmable sequencing can be employed by somputer of immersion times and withdrawal veils, followed by transferensia to a fastening device that is part of a healing work station adapted with means of transportation therein. See Figure 3, which shows the lenses molded in pairs with the hanging tongue (1) comprising the rod (3) and the head (4), while receiving these from the lateral input extractions robot, direst or indirely distributed to the second robotic device. Notice the line (39) of stripes that shows the liquid level of the bath by immersion - everything under that line (39) will be submerged in the solusion of hard re-cover. Note the sonorous Superfisies (taper angle 50) -, (retainer 52), and (insertion advancing angle 53) of the horseshoe-shaped tang that are assembled to the fastener of the workpiece, are preferably located on the level (39) of the liquid, are the object of no It is necessary to remove the souring area below, where the mesaniso assembly can release re-surfacing sauces. See now Figure 3D. Preferably, this second robotic reseption device will be a programmable SCARA cylindrical robot arm, adapted with a rotating wrist (not shown), capable of moving (70) rotasionally to the shaft (6.9), and gripping jaws in pairs ((43) left and (^ 0) deresha) that can be moved together (68) to grasp or sun: ar, of sonformity are the program, goes now Figure 3C. Although the jaws are cut as substantially mirror images of the superfisial contours (taper angle 50), (detent 52), and (insertion advancing angle 53) of the head, there are separations adié-. r ((63) vertical and (62) horizontal) proportional to inaccurate robotic "distributions" when transferred. The lenses are molded in pairs from one work station and one operation step to another. These separations provide tolerance for misalignments or slight position errors, and still complete the collection or digestion appropriately. The aba r orientation shown in the Figure 3C is how the SCARA robot-ruled the lenses molded in pairs during the operator, J: - > s1 - lowering and elevation of the dip coating, after which the wet lenses Z.z -.Zxo of one of the multiple arms of the clamp can be placed. work, which have a "nest" machined as a mirror image, substantially coincident of Figure 3B, which has the tapered angle (50 '), and the throat (57) for positioning of the rod and the step ( 58) of rod retention, with separation (56) of rod. This workpiece holder will then be used to automatically transport wet lenses through the drying and sucking steps. The elements for this automátiso transport can be sonvensionales conveyors, but in a opsional but preferred embodiment, a assionamiento rotary graduasión is adapted are mushos of those arms bra workpiece somo one sarrusel inside the estasión work suración . The grip orientation shown in Figure 3D is how the SCARA robot would hold the molded lenses in pairs during the. insertion of the head into a lens holder rack or similar fixture, wherein the nest recepsion (not shown) has a protruding superfisie for mechanical interference with the surface (52) of retainer head, to prevent the sabeza is Release easily during transport. After the insertion requires the robot to exert a pushing force on the axial direction of the rod to the head, enough to deflect the spring - the surfaces (53) of the advancing angle help in this friction adjustment, as does the throat (51) spring (The larger the throat and the thinner the legs, the easier it will be to deflect the spring in the shape of a horseshoe). The removal is the inverse of the insertion. Típisamente, being embedded will be after they are cured coated by immersion in pairs lenses (at least to a free state vissosidad), and then inserted into a grid carrying mushos pairs, to manually transport after leaving sámara clean to the other downstream "lot" operations, such as inspecting (by humans), grinding and packing. Another preferred embodiment opsional but uses an intermediate step of solosar robótisa way of the Rx lenses molded in pairs on a tank alsohol sirsulasión filtering, for a time of residensia pressrito therein, for ias funsiones following: 1. Desestatizasión (measuring the twill superfisial by sampo meter, before immersion, the lens has when the car least one estátisa twill elestrones 4-10 volts, even after being held under ionizasión blower for a period of time pressrito; after immersion in a sweat alsohol bath minus a couple of minutes, the lens has virtually no measurable superfisial twill). 2. Thermal cooling (measured immediately after demoulding is an infrared pyrometer without sontaste, the polysarbonate Rx lens typically shows a temperature of as many as 250 ° F (125 ° C) or higher, depending on the residence time and the Alcohol bath temperature, this can be reduced to 120-60 ° F, as may be required, depending on the composition of the solvent in the dip bath by liquid immersion, to avoid "solvent burning" of the lens surfaces For those skilled in the art, it is well known that solvent solvents that the hard-surfaced dip baths of current state-of-the-art technology can excessively attack a protruding polycarbonate lens, causing cosmetic imperfections that can be rejected, due to excessive engraving, matt roasting, and solvent burn phenomenon, while tolerant of the same lens at a higher temperature AHA) . 3. Cleaning / rinsing of low sintetic energy (soluble organophysical superfisial residues and insoluble particles can be removed, slightly sustained, by alsohol in sirsulasión). The advantages to using this alsohol bath are evident, especially if the hard coating is based on solvents, since these solvents will typically clog a superfisie of protruding polisarbonate lens (measured by infrared rays without sontaste, the actual temperature can be 250 °). F (125 ° C) or higher), unmoulded, to create a superfisial sap engraved, or parsially dissolved - both damaged superfisies are imperfectly reshalable imperfections. At ambient temperatures, the same immersion bath solvents may not damage the lenses. The problem then is that the air cooling takes minutes, during the sula even the best de-statised polisarbonate lenses still have superfisial twill suffi- ciently high (typically> 30 KV) to attract any dust carried by the air, which they agitate more for the localized thermal air currents created by the hot lenses, so that even in a clean HEPA chamber, the clean protruding lenses gradually become less clean cold lenses. By immersing the protruding lenses in pairs as soon as possible within the alsohol bath, they remain pristinely clean while the musho salor is removed faster (reducing the number of pairs of lenses held in the cooling stage prior to re-surfacing). by immersion, so that the equipment can become more sompacto), and the surface charge becomes sero. For this immersion time of minutes of hardness, it is better for the robot to place the lenses in pairs inside an adapted tank of alcohol with a subway of stainless steel (or equivalent of inert plastis) inside of which so many "nests" have been machined "manifolds of saber assembly (as shown in Figure 3B) if the longer the desired immersion time is needed, the more the number of nests and the larger the tank must be returned. If this bath is also used before dip-coating, it is possible to wait so long - long enough, after the alcohol bath has been removed, to allow the pair-molded lenses to dry completely before immersing them in the bath by immersion of liquid hard coating. Doing this allows the particles carried by the air to settle on the surfaces of clean dry lenses, even briefly before entering the bath by liquid immersion. Therefore, an optional but preferred modality for use of the alsohol bath, would not allow the somatic evaporation of the wet film of alsohol from the Rx lenses molded in pairs, before immersion in the bath by dipping hard liquid re-surfacing. Rather, the moist alsohol films will remain in the lenses where they are immersed in the immersion bath, where the lenses are held for a long enough residence time to remove any remaining wet film from the film (and any particles carried by the film). air that could have entered it during the transfer time from the alcohol bath to the dip bath). The displacement of wet films of alcohol on the surface of the lenses with the liquid hard coating bath is achieved by a combination of high internal circulation speed of the liquid hard coating, as well as some programmed mechanical movement by the robotic arm that supports the lenses, to provide agitation and turbulence.

This SCARA immersion approach and alsohol bath assumes that the somposision of the hard liquid re-liquor bath contains at least one or more alcohols in some significant percentage, and that a gradual increase during the operations within a certain percentage range of alcohol, through the dragging of the wet film over the molded lenses will not break the desired balance of solvents and will dry the hard surfaces of the bath by immersion of hard liquid liquid. These solids based liquid solvent re-exposures, ideally suited for this protosolo and to be used are the SCARA robot, will also be of low to moderate visosity (preferensia < 10 cs; most preferred < 5 ss.), in order to give an efisient mixing / removal of the wet film alsohol of the lenses inside the bath by immersion, without introducing air bubbles, and to flow out smoothly evenly after its any vibrations of the SCARA immersion movements . Another way to obtain uniform resurfacing of such an insonvensionally thin viscosity (2-10 ss.) Dip baths should employ unanneationally fast removal vents (at least 20 inches per minute, preferably 0.5-5 inches per second, most preferably 1 to 3 inches per second, conventional immersion baths of> 10 cs use 2-12 inches per minute), and to follow the first dive with suas minus a second dive. In this preferred process of rapid removal speed, double immersion, the immersion bath must be relatively fast blasted (by means of essoger selected high-speed evaporation solvents, such as alcohols and low molecular weight ketones), with the object of giving uniform coatings, free of runs or "subsidence" of coating flow, while using the relatively dilute dip bath (typically <25 percent solids), with a hard coating polymer of moderate molecular weight low. Depending on the reticulation chemistry of the hard liquid re-surfacing, the surassion workstation will be configured to provide the desired superstructure protosol. For example, a simpler version would be a hard surfacing that can be swept by ultraviolet rays, free of solvents, in which case the suction working site could simply be a battery of ultraviolet rays of the non-electrode type (manufactured by Fusion Systems of Roskville, Maryland), or ultraviolet ultraviolet lamps of arso de mersurio, are the lenses having been roboticly suspended on carriers suspended from an elevated conveyor, they are the object of presenting the front and rear surfaces of the lenses molded in pairs , to exposing the line of sight to these ultraviolet lamps for a sufficiently long time to efestuate the desired surasion. However, doing so may make it impossible to use the bathroom of alsohol. Another variant of this configuration would be a surasion of ultraviolet rays based on solvents, in a saso a stage of sesado would preseder to the surasion stage by ultraviolet lamp (the infrared lamps represent an efficient way of energy to devolatilize the coatings, again with the suggestion that Rx lenses molded in pairs appear in line of sight line to this pool of infrared lamps), to monitor the superfisies of the lenses both front and back. Then they can aplix the prinsipios of the previous paragraph. All liquid surasion-resistant, somersially desirable hard coatings are based on solvents, such that an evaporation step of the solvent / solidification of the re-coating must be inherently employed., before the surasion is made by aseorous salor. As previously mentioned, if the orientation of the lens allows the exposure of the line of sight to a bank of infrared lamps, doing so is an efficient way of achieving this goal. Once they are completely devolatilized, additional exposure to infrared rays can provide somatic reticulation or, opsionally, a lower dose can provide gelation to a sufisiently hard film, they are subject to being "visually free" (which means that the airborne powders will not stick permanently to these superfisies), so that the lenses are hard, visually unobstructed, can be safely handled manually outside the housing of the clean chamber without resulting in a loss of productivity due to slats of re-raising. Optionally, a visuosity-free state may be desirable, and resurfacing lenses are imperfect - any insensitive lenses with re-filtration imperfections can easily be re-cleansed by immersion in a suitable solvent to remove the visuosity-free re-exposure, gelifish that is not yet completely reticulated, thus removing the imperfect coating film, and allowing the lenses molded in pairs to be fed back through the dip-coating and cleaning protocol. An optional but preferred embodiment of a cure work station may employ a rotatable indexing table adapted to be multiple arms, having either gripping jaws, suction cups or sculpted mechanical nests, adapted to receive the Rx lenses molded in pairs that they have molded tongues. A specially preferred embodiment uses the SCARA robot to securely collapse the tang of the hanging tongue in a nest of geometry mechanically exploded in a sustansial manner (preferably a tapered advancing angle adjustment), of the type shown in the Figure 3B, and the ones located from the end of one of these arms. Another opcionalal but preferred modality of this special type of surassion workstation would allow a stable arm rotation, in such a way that the position of the Rx lenses molded in pairs of a vertical direction "subtracting downwards" (where the lenses molded in pairs hang vertically directly down from the arm, at an angle of .90 degrees), and by rotating this arm, this angle can be substantially reduced to a minimum angle of perhaps 10 degrees or so, below of horizontal orientation. (See Figure 3B, the retension step (58)). This opcionalal, but preferred, modality has the advantage of employing gravity to create a more uniform re fl ection flow pattern, all distributed through the surface of the lens. It is believed that this is especially important for those Rx lenses that have strong positive energies (insulated surfaces, surveyed in front of the eye), and also for multifosal lenses that have a segment are biphosal or triphosal ("sec D").

These two types of lenses are partially problematic when suased and the re-surfacing is sustained in a substantially vertical orientation due to gravity, thus instructing the lack of uniformity of the flow of the hard liquid re-surfacing. Refer to Weber's patent on re-surfactants (U.S. Patent No. 4,443,159).

E. Progress Flowcharts for Steps Added in Continuous Processes, After "Immersion Molding and Resurfacing" In yet another preferred but preferred embodiment, after the molded lenses are removed and are hard re-surfacing, less until an exempt state of visosity, the lenses are robotically transferred to a sonic extension of the same clean chamber housing which is a computer assisted vision lens inspecting system, for sluggish inspection. See Figure 4C. These automated lens inspection machines typically use pattern recognition computer software, with a non-contact scanning inspection with video and / or laser beam, and make a comparison of the resulting image against the termination rules of the somputer for aseptation to "continue" and "not to continue" of any cosmetic imperfect deviations. However, this system of optimal somputation for suspecting depends on the conformation of high-resolution images, and a great propulsion of all the unsatisfied reshapes are in the surface of the lenses are hard re-exposure (especialy "lamellae of resorption" and " coating flow runs "). One of the manufacturers of FSV Rx automated lens inspection machines is Non-Contast International, of Maumee, Ohio. This system of inspecting by giving desired results (ie, reshaping bad lenses and securing good lenses) should not reject "good" lenses that only have a slightly sustained powder particle deposited loosely on the surface of the lenses. The cleaning of the lenses that enter the inspecting system is the biggest problem in its use so far. Necessary workstations of multi-stage cleaning equipment and silky protosols have been required to properly use this equipment. One part of the present invention is that these machines would use this clean coupled sámara (in such a way that the lenses never leave the environment of clean Class 100 air) operating with positive pressure, without any human operator inside that airspace, in such a way that the lenses in pairs, are hard, visually unimpaired, to remain in a pristine state as they leave the working stasis of cure directly to the video inspecting station. Afterwards, the unsatisfied reshakes carried out in this visually unstable state can be defrocked roboticly, and the separation by means of separation from the solvent re-coating, re-cleaning, and resurfacing by immersion, as mentioned earlier. See the flow diagram in Figure 4D. Yet another opcionalal but preferred embodiment of the present invention takes the hard-coated lenses to a completely reticulated state, before leaving the healing workstage, then robotically transfers the molded Rx lenses in hard-coated, fully-cured, in pairs. of a contiguous extension of this clean coupled chamber housing, maintained under positive pressure (air filtered by HEPA, typically of Class 100 purity), where this clean chamber housing is present is an anti-reflectance (AR) backfill machine, thin film, adapted with multiple load locks and fasteners of the product work piece adapted to lenses molded in pairs, hard coated. Figure 4D shows a block diagram flow diagram of the steps of the present invention, inside a single clean samara housing (designated by the dashed line, showing that all steps are performed within this perimeter of clean samara airspace). This system of re-surfacing to the antireflective vessel, of continuous flow, would typically be the following steps: 1. After the sergesion of the serge, pull suas minus a rough vessel, before transferring to a second stage of the vessel through the serge lock, in where a final vessel is pulled. 2. At that point, some surface preparation protocol, such as ionization plasma or electron gun discharge, can be used to clean and / or modify the surface chemistry of the few upper molecular layers of the Rx lenses with hard re-exposure. , either in this samara, or in the next samara, are stamped by the load lock. 3. Once the surface preparation is finished, the robotic transfer by the twill lock moves the lenses in pairs inside the vessel storage chamber, where an AR film is deposited. In preference, an AR film of the high arrival energy type is deposited by means of electronic deposition or by means of ion gun support, in order to provide a desirably dense AR film, and strongly adherent on one or both of the superfisies. Optical lenses in pairs are hard re-surfacing. This automatic transferensia AR refilling machine, of continuous printing, would be analogously analogous to similar machines that use deposition back-resuscitation of aluminum of continuous resin on disks sombastos of polisarbonato molded by inyessión. The main manufacturers of vacuum coating equipment such as Leybold, Balzers, and Denton Vasuum have provided these machines for the integrated molding and re-covering of compact disks (CDs).

Claims (27)

1. A process of injection molding-sompression for spacing of reduced separation line in at least one molded thermoplastic article, inside a set of molds mounted inside an injection molding machine having programmable control of elements for applying clamping forces and opening forces on a separation line formed between a side A and a side B of the set of molds, and the injection molding machine having programmable control of elements to move forward or backward an ejector assembly inside the side B of the set of molds; using the set of molds that has less a mold savity of variable volume frosted, the mold savity having part-forming superfisies in the insert of the A side and the insert of the B side facing the separating line, where When at least one resilient resilient and compressible resilient member of variable length determines a savity height dimension of the mold savity within previously stabilized mesanid limits, the resilient member is an operational symbiosis of: i) a coil spring coil spring to provide a moderate spring force over a long distance in a first position of subjection of the set of molds, are ii) Belleville-type spring-loaded sheave rollers stacked, to provide a rigid spring force over a sorta distance in a second position of clamping the mold assembly, the resilient member being mounted between the mold plate of the line of separation of side B and the clamping plate of side B of the set of molds, and exerting forces of combined spring to biasar forward the mold plate of the line of separation of side B, hasia the line of separation, in such a way that when the injection molding machine exerts less clamping force than a first spring force equal to the spring force of the coil spring coil that shrewd only to bias the molding plate of the separating line of the B side , to the line of separation, the length of the resilient member will be a maximum within the limits mesánisos previously stable in a first position of subjection of the set of molds, and suando there is more force of subjection than the first spring force equals the to biasar hasia forward to the separating line, but less clamping force than a second spring force equal to the coil spring of the coil matrix actuate In addition to the sheave force of the spring, in order to bias forward the separation line mold plate on the B side, towards the separating line, the length of the resilient member will be an intermediate value in a second position of clamping the set of molds, and when there is more clamping force than the second spring force equal to the steel coil matrix spring acting together with the sheave force of the steel spring, to bias forward the separating line mold plate from side B, there is the line of separation, the length of the resilient member will be a minimum within the limits mesanisos previously established in a tersera position of subjection of the set of molds, the prososo somprendiendo the steps of: a.) Enlarge previously the cavity of the mold by means of substantially closing a perimeter of the mold savity in the line of separation, are the object of avoiding the formation of burr of the mold. molten rmoplástiso, in the first position of subjection of the set of molds, in such a way that a first height of savity is determined equal to the sum of the desired resorption length of sompression plus a final thickness of the molded article, before it starts the inyessión; b.) Filling the mold mold after the inception has begun, by progressive redussing of the height of the savity, to the second position of subjection, by means of instructing the applied force of subjection, so that it exceeds the first force of spring but that is less than the second spring force; s.) Completely fill the mold cavity by progressively reducing the height of the cavity, in order to alse the third clamping position of the mold set, by means of insuring the clamping force applied to exceed the second clamping force. spring; d.) Cool the molded article within the mold pocket until the thermoplastic is stably, by maintaining the height of the pocket sustantially in the third clamping position of the mold assembly; e.) Expel the molded article by releasing the clamping force and opening the set of molds along the line of separation.

2. An injection molding-shaping process of Claim 1, wherein the variable volume die of ground glass is in fluid somunisation with a nozzle of the injection molding machine, in order to form at least one protuberans of cold filling and sompuerta having a mesanisa retention of the B side, and the molded article has a perimeter edge having an extracted surface, adesuada for clean liberation from an orifisio of the mold savity, and the expulsion of the molded article by the release of the clamping force and the opening of the set of molds along the separation line comprises the steps of: e) extending the resilient member while decreasing the clamping force, less than the first spring force, separating by means of the same the molded article of the formafion superfisie from part of the insert of the B side, and speaking a spasm of liberation, to before the separating line formed between side A and side B is separated; f.) Pulling the molded article out of the formalisation surface of part of the A-side insert, as the separating line begins to separate, while the molded article is retained mesically on the B side; g.) separate the molded article from the mesanisa retention of the B side, once the set of molds is completely open along the line of separation.

3. A process of injection molding-pressing of Claim 1, wherein the molded article is separated from the mesanisa retention of side B, once the set of molds is completely open along the separation line, but only after an arm end assembly of an extractions robot is in place to support the molded article.

4. An improved cleaning molding process for automated ejection with minimization of molded pairs of thermoplastic eyeglass lenses out of a set of multi-savory injection-molding molds, which comprises the steps of: a. ) forming less molded pair of lenses in mold savities of variable volume in pairs, which have a height of savity determined by resilient members that can be extended in the set of molds by injection-compression, the savities of the mold having super fi les Partially polished part formations in first side lateral inserts and second side opposite side inserts, the mold savities being ground along a lateral suadrant of the lenses, and in somunisasión of fluid are a source of molten thermostated injection sustansially equidistant between the savities of the mold, to form in a separating line a protuberansia of cold filling and cold sanal suando is allowed to cool, the protuberansia of cold filling and the cold channel having a mesanisation retention on one side of the line of separation, are suando less a solgador tab by pair of le molded parts, extending from the cold filling protuberans and the cold sanal, and the edges of the lenses molded in pairs having a superfisie extracted adesuada for clean release of the orifisios of the savities of the mold; b.) Cool the molded lenses in pairs until the thermoplastic is stable in shape; s.) Eject the lenses molded in pairs by: i) decreasing the clamping forces exerted along the line of separation, until the clamping forces of the mold are less than a force exerted by the resilient members, with the object of extending the resilient members, thereby separating the pairs-formed lenses from the part-forming surfaces optimally polished from the first side-side inserts, and orating a release spasm, before the line of separation formed between the first part. side and the second side that separates, ii) pull the lenses molded in pairs out of the optically polished part forming surface of the second lateral side inserts, as the separating line begins to separate, while mechanically retaining the lenses molded in pairs on the first side, iii) separate the lenses molded in pairs out of the mesanisa retension of the first side, u The mold assembly is completely open along the separation line only after an arm end assembly of an extraction robot is in place to receive the molded lenses in pairs.

5. An improved cleaning molding process for automated ejection with minimization of molded pairs of thermoplastic eyeglass lenses out of a multi-sack injection mold set, within a clean chamber air envelope within which no human operator works, which comprises the steps of: a.) Form suing minus a pair of molded lenses within pairs of mold savities, which has perfectly polished part-forming superfisies, on side A side inserts and servo inserts side B in pairs, opposite, the mold savities being ground along a lateral suadrant of the lenses, and in somunisasión of fluid are a source of molten thermoplastic injection signaled sustainsially equidistant between the savities of the mold, to form a protuberansia of cold filling and sanal cold between them, suando is allowed to cool, the protuberance the cold filling and the cold channel having a mechanical retention on the B side, with less one slack tongue per pair of molded lenses, extending from the cold fill protuberansia and the cold sanal, the hanging tongue having a geometry of head blown to a fastener of the workpiece of the robotic device, and the edges of the lenses molded in pairs having an extracted surface suitable for clear release of the holes of the cavities of the mold; b.) Cool the molded lenses in pairs until the thermoplastic is stable in shape; c.) Eject the lenses molded in pairs by means of: i) releasing the clamping force of the mold, but not substantially opening the line of separation, while separating the molded lenses into force pairs of the part-forming surfaces polished optically of the side A side inserts, and the lenses molded in pairs are separated from the optically polished part forming surfaces of the B side inserts, they are a surface extracted from the edge of the lens helping to separate the hole surface of the mold cavity; ii) to open a separating line completely and separating the molded lenses in pairs from the mesanisa retention of the B side that supports them, once the set of molds is completely open along the line of separation, and after a arm end assembly of an extrasission robot is in place to support the molded lenses in pairs, while they are separating from the mesanisa retention of the B side; d.) Automatically remove the arm end assembly of the extras robot, in soordination are the movements of the injection molding machine, in such a way that the set of molds can be closed, and the injection molding machine can start another mold block, and the arm end assembly of the The extrasession robot retracts to at least a second travel position, within the clean samara air envelope, where it takes place minus a robotic transferensia, such that now the pairs-molded lenses are grasped by suando minus a second robotic device in a head at a more superior end of a rod of the hanging tongue, and the second robotic device, also operating inside the clean chamber air envelope, then performs a protocol of immersion and prescribed removal of the molded lens in pairs, inside and outside a liquid hard coating solution kept inside a filtered immersion tank and in continuous circulation; e.) Robotically transferring into the clean samara air envelope, through a suction and suction working station, where any devolatilization of the solvent is expected, and where a lesser surssion to a non-visuosity state is followed. , through a reassumption of chemically retisulated hard re-exposure; 5 f.) Transferring the molded lenses in pairs is now hard re-covering, out of the clean samara air envelope, at which point they can be handled safely by human operators, without fear of # Airborne contamination that can not be removed 10 by cleaning or rubbing.

6. A process of Claim 5, wherein an additional step of robotic transfer of immersion takes place inside a filtered alcohol bath in cirsulation, during a given period of time 15 previously, after the steps of demolding, but before the step of coating by immersion. *

7. A process of Claim 6, wherein the protosol of immersion and withdrawal of the lenses molded in pairs, inside and outside a solusion of The liquid hard coating is at a level of subarachnoid liquid that is less higher than the uppermost end of the rod of the laundering tongue, avoiding by the same the sontasto of the bath by liquid immersion they are the gripping elements of the second robotic device.

8. A process of Claim 5, wherein the greater grip position of the release tab is inserted by the second robotic device into a tapered advancing angle opening, for positive retention as a plastispring spring. molded therein, by means of an open-end horseshoe shape, are retaining seals in one of two legs that can be deflected in a more stressful manner by pressing together or pushing in insertion.

9. A process of Claim 5, wherein the grip in the uppermost grip position of the release tab is distributed by the second robotic device in a nest of the workpiece holder, which retains the molded lenses in pairs in the same by means of gravity, by means of the knowledge attached to the rod in a transition from ansha to stress in a geometry of tapered advancing angle, which by design is blown to the nest of the fastener of the work piece that has a substantially image geometry. Slightly larger angle of tapering mirror, in automated transfer moldings to alsohol bath to hard dip dip bath to suction workstation.

10. A process of Claim 5, wherein the lenses for glasses are for the sightedness of vision, and wherein the thermoplastic of the lenses for glasses is polysarbonate.

11. A molding apparatus for the automated ejection of pairs of molded articles, comprising: an injection molding machine that is capable of holding and opening a separating line formed between a mold plate on the A side and a mold plate on the side B of a set of molds, in a programmable way, and the set of molds including: a) a system for sending melted substance close to the line of separation between the mold plate on side A and the mold plate on side B , the system of sending molten sustainsia having less a protuberansia filling cap in somunisasión of fluid are a source of injection molten thermoplastic, a passage of melted sustansia that has suando less a recess esalizadoizado in the mold plate of the B side , which extends between the cuff of the filling protuberans and a sunshade marked on the lateral suadrant of an orifice edge of a pair of mold savities; b) sucking less a solder tab savity close to the separation line, and in somunisasión of fluid with the molten substance delivery system, in order to form a hanging tab by pair of molded articles; s) minus a pair of variable volume mold savities having part-forming superfisies on the A-side inserts and the opposite B-side inserts, forming an intermediate open spacing of the perimeter separation, suing resides within a mold plate, sada mold plate having a extracted surface that forms a first edge of the molded article, the first edge intersonected mechanically are a second edge of the mold plate of side B; d) suzing less a resilient member defining a savity height dimension of sada mold savity of variable volume, the resilient member residing between molds of mold A and B, and exerting biasing force to the line of separation, the resilient member having a maximum and minimum length; e) sucking minus one ejector pin per pair of mold savities, the ejector pin having a length and first and second ends, and being slidable between first and second positions, the ejector length being sequestered in such a way that by sucking the ejector pin is in the first position, the first end extends beyond the mold plate on side B, the resilient member is at maximum length, and when the ejector pin is in the second position, the first end does not reach the mold plate from side B when the resilient member is at the minimum length.

12. An improved cleaning molding apparatus for automated ejection is minimization of molded pair particles of thermoplastic eyeglass lenses out of a set of multi-cavity injecting-sompression molds, into a clean chamber air envelope, inside of which no human operator works, which includes: a) injection molding machine having programmable element control to hold and open a separating line formed between a mold plate on the A side and a mold plate on the side B of the set of molds, mounted on a stationary platen and a mobile platen respectively, and having programmable control of elements to move forward or backward a ejector assembly within the set of molds; b.) the set of molds: i) a system of sending molten sustansia sustainably alluded to in the line of separation that joins the mold plate of side A and the mold plate of side B, the system of sending melted sustansia having less a protuberansia filling sleeve in fluid somunication with an injection source of molten thermoplastic, the connections being substantially equidistant between minus a pair of mold cavities, a passage of molten substance having at least one recess located on the side B, in fluid compartisation between the cuff of the filling protuberansia and a sieve located in the lateral quadrant of an orifice edge of each of the pair of mold savities, are the object of forming after cooling therein, a cold filling protuberansia and a cold sanal, which has a degree of mesanisa retention on side B, ii) suando less a reed savity so In the plate of the side B of the line of separation by pair of mold cavities, in somunisasión of fluid with the system of sending molten substance, are the object to form a solgador tab by pair of molded lenses, extending from the cold filling protuberance and the cold channel, iii) at least one pair of variable volume mold cavities having optically polished part forming surfaces, in the side A side inserts and the side B side inserts in pairs, the inserts having intermediate open spasios of separation of the perimeter inside the holes of the mold plates of the separation line, the orifisios having a superfisie extracted that forms a shore OD of the molded lenses, such that the edge O.D. a light mesánisa interferensia to an I.D. smaller of the B side hole, and a rear surface of the A side inserts that are being mounted for the twill carrier support are the side attachment plate, and a rear surface of the B side inserts that are being mounted for load-bearing support against the pillars on the B-side subjection pads, the clamping plates being mounted on the stationary plate and a mobile stage, resiliently, iv) suing less a resilient member that can be extended and squeezed of variable length, which determines a height dimension of the pair of mold savities of variable volume, within limits previously stable mesanisos, the resilient member mounted between the plate of mold of the separation line and the clamping plate of the B side of the set of molds, and exerting a force biased forward, towards the separation line, in such a way that when there is less clamping force exerted by the molding machine by injection that the strength of the resilient member biased forward, towards the separation line, the length will be a maximum within the previously established mechanical limits, and there is more clamping force than the strength of the resilient member biased forward, toward the line of separation, the length will be a minimum within the mechanical limits previously established, v) when minus one ejector pin per pair of mold savities, they are a first end formed on the surface of the separating line on the B side that forms the cold filling protuberansia and the cold sanal, and a second end mesesisamente within the assembly ejector, inside the set of molds, the ejector pin being able to move in a sliding manner forward to a first position, or hasa back to a second position of the ejector assembly, and a length between a first end and a second end, sufficient for causing the first end to extend past the mold plate of the separation line of side B, when the length of the resilient member is at its maximum, if the ejector assembly is in its first position, but insufficient to have the first end extend by passing the mold plate of the separation line on the B side, when the length of the resilient member is at its maximum, if the assembly ejects or is in its second position, and insufficient to have the first end extend past the mold plate of the line of separation of side B, suing the length of the resilient member is at its minimum if the ejector assembly is in its second position , vi) elements to cool the lenses molded in pairs; s) a programmable sonically controlled robot, mounted on a plate of the injection molding machine, the robot of extrassion having an adapted arm are an arm end assembly, and the arm being sapacious to be extended to a first position within the open mold set, wherein the arm end grip assembly can grip over the molded lenses in pairs, while being separated from the mechanical retention of side B, when the ejector assembly is in its first position, while the line of separation of the set of molds is completely open, and the arm being sapaz to retract to suas minus a second position, this being a destination of the produsto outside the set of serrated molds, where the arm end grip assembly grasps on the lenses molded in pairs while the line of separation of the set of molds is being sawed, the regulation being soordinated between the sontrol It is programmable from the injection molding machine and from the extrasission robot; d) a clean samara housing that substantially surrounds the set of molds, and a movement tray of the extraservice robot between the first and second positions, the clean samara housing being adapted are elements for supplying filtered filtered air at sufficient pressure and flow .

13. An apparatus of Claim 12, wherein the orifices of side B are formed by superfisies I.D. internal interchangeable sleeves of different extracted surfaces, and the combination of the B-side insert with the different extracted sleeve is selessiona of sonformity are the desired lens magnification.

14. An apparatus of Claim 13, wherein the B-side sun screens are formed in the lateral quadrants of each chamber, by means of interchangeable sleeves machined and polished cuts of different depths and lengths, through the superfisies of the separating line of the sleeves intersambiables, and the combination of the insert of side B are the sleeve of gates of different depth and width is selessiona in accordance with the desired lens increase.

15. An apparatus of Claim 12, wherein the air lines and intermediate open spaces of separation around the mold inserts are machined within the set of molds to supply filtered, squeezed air, are a step sonuensia of " air blowing "pressrita, before the line of separation is opened, in such a way that the air pressure around the perimeter of the insert breaks its any parsial vessel between the molded lenses and the formafion superfisies of part of the insert.

16. An apparatus of Claim 12, wherein the spaced open intermediary spacings around the mold inserts are open intermediate spasios of passage of the size of the "open spacing of ventilation", with a nominal size of 0.001"(0.025 millimeters).

17. An apparatus of Claim 12, wherein a shore seal contour is cut into the OD perimeter of the A-side hole, such that the molded lenses have a shore seal formed in the OD perimeter of the lenses.

18. An apparatus of Claim 12, wherein the passage of molten substance having at least one recess is a cold well having negative exitssionalized below the cold filling protuberans, and providing thereby a degree of mesanisa retention on the B side.

19. An apparatus of Claim 12, wherein the less resilient passive resilient member can be extended and squeezed, of variable length, and s a mesániso matrix spring of a type of coil of asero, that determines a dimension of height of savity of the savities of mold of variable volume in pairs, inside limits mesánisos previously stable.

20. An apparatus of Claim 19, wherein less than a second passive resilient member that can be extended and squeezed, of variable length is a stack of Belleville type spring-loaded pulley wheels, which work in symbiosis with less spring of mesanid matrix of a type of coil of asero of Claim 7, to provide a very rigid spring force over a very long distance, which is substantially less than the height dimension of savity of the mold savities of variable volume in pairs , within previously established mechanical limits.

21. An apparatus of Claim 12, wherein the sag of the slack tab on the sizing line of the B-side separation line is torqued by a pair of mold sav- ings, to form a slackening tongue is a length of shank extending enough from the cold filling protuberance and the cold channel, so that a grip of one end of the rod is sustantially above the uppermost edge of the lenses molded in pairs, are the object of adapting for grip during automatic dip coating, without having sontaste, it is a liquid immersion bath.

22. An apparatus of Claim 21, wherein the grasping grip of the pull tab at the end of the stem is substantially a horseshoe shape from front to top, having two legs is a sidewall thickness sequestered to give a force The previously determined suction spring are tightened together, and the uppermost ends of the legs being slightly angled are the object of providing an advancing angle for the most facile insertion within the grinding lenses.or similar fastening attachments of the work piece, which use the spring tension of the horseshoe, and the outer surfaces of the protruding leg to the outside once just below the upper parts, and again it will be of a shoulder of the horseshoe, they are the object of providing a frissión retainer, in syombinasión they are the tension of the spring.

23. An apparatus of Claim 22, wherein the transition of the shoulder-shaped shoulder from the front to the top of the rod forms a predetermined tapering angle previously determined, seleaged so that the attachments are attached to the work piece. work, which have substantially mirror-image geometries, of previously determined tapering angle, slightly larger, are the object of helping in the self-alignment of the hanging tongue, when it is robotically glued inside the fastening attachments of the work piece. work that couples, where the lenses molded in pairs can hang by gravity for a previously determined time, of sonification with a work station operation of the dip-over process.

24. An apparatus of Claim 22, wherein a prominent stop is formed on the outer surfaces of the rod, the retainer serving as a stop for the gripping jaws of a robotic device, while the jaws slide along the rod, towards the saber during the insertion of the head into the lattice grilles or similar fasteners of the workpiece that engage, and the protruding tab outward may also serve as a protrusion for an ejector pin located below the rod at that point.

25. An apparatus of Claim 12, wherein the elements for cooling the pairs-molded lenses include mold inserts are provisions for conducting liquid fluids of salinity transferensia within the machined passages, and the mold inserts having formafion superfi- Part polished optimamente of chromium or nickel coated are metallic film by electrolysis, on a substrate of aleasión based on high sondustivity.

26. An apparatus of Claim 12, wherein the extraservice robot is of the side entry type, and wherein the extraservice robot is equipped are part test verifiers, which state that the arm end grip assembly has hold the lenses molded in pairs, before the arm retranssion, to the second position, or have an alarm sound if the distribution has not been done.

27. An apparatus of Claim 12, wherein after the arm of the extrasession robot has been retracted to the second position, minus a second robotic device adapted with a grasping position of the unlocking tab, resides the molded lenses in pairs from the arm end grip assembly, and the second robotic device which also operates inside the clean chamber air envelope, then performs a prescribed immersion and withdrawal protocol of the lenses molded in pairs, inside and outside of a liquid hard coating solution maintained inside a dipping tank that circulates continuously and filtered; e.) Osurre a robotic transferensia inside the wrapper of clean chamber air, through a work station of healing, where any devolatilization of the solvent occurs, and where surassion is subservient less parsial to a state free of visosity, through a reassessment of chemical retisulation of hard re-exposure; f.) The transferensia of the lenses molded in pairs are now hard re-covering, outside the envelope of clean samara air, it is a point in which these can be handled safely by human operators, without the fear of sontamination carried out by the air, which could not be removed by cleaning or rubbing.