Abstract: An apparatus for injection molding a product having a partly thin portion includes a molding die including a male die and a female die for defining a cavity having a volume larger than a volume of the product. A gate is provided to permit molten resin material from an injection molding machine to be injected into the cavity. A slide block disposed in either the male die or the female die has in cross section a dimension corresponding to a dimension of the thin portion of the product. The slide block is movable between a retracted position where the volume of the cavity is substantially maintained and an advanced position to project into the cavity to form the thin portion. A drive is provided for moving the slide block to the advanced position before the resin material injected into the cavity is solidified.

Abstract: This invention relates to a hot tip gated multicavity injection molding system wherein an elongated heated probe extends centrally in a straight portion of the melt passage leading to each gate in a position wherein a tip end of the probe is centrally aligned adjacent the gate. One part of the straight portion of the melt passage is formed by a locating sleeve which is seated in the cavity plate and has spaced pins which extend inwardly to contact the outer surface of the probe to accurately locate the probe with the tip end in central alignment with the gate. Each probe has a central heating element with a double thickness portion extending to provide additional heat where the pins contact the probe. One of the pins is hollow to receive a thermocouple to measure the temperature of the melt flowing past the pins.

Abstract: This invention relates to an injection molding system having two heated nozzles mounted in tandem. The rearward nozzle is considerably longer than the forward nozzle and has a melt bore which is considerably larger in diameter than the melt bore of the forward nozzle. The smaller forward nozzle has a backplate secured to its rear end with a thin flanged portion which extends outwardly and rearwardly into bearing contact against a rearward mold core to secure the forward nozzle in position in a well in a forward mold core. The rear face of the backplate has a seat extending around the melt bore to receive a cylindrical forward portion of a gate insert mounted on the forward end of the rearward nozzle. Thus thermal expansion of the larger rearward nozzle is taken up by the forward portion of the gate insert sliding in the seat.

Abstract: The front panel of an air conditioner unit or the like, including a louver-like intake grill comprising several transverse slats with outward-upward inclination is formed by injecting molten resin into cavities formed between a stationary mold and a movable mold along a parting line thereof, the molten resin being thus injected through pin-point gates formed on the stationary mold side and tab gates constituting parts of respective cavities and provided on the stationary mold side at part corresponding to the upper edge faces of the slats, the pin-point gates being connected to the upstream parts of the tab gates. By this method and apparatus a high feed rate of the resin is obtainable, and the molding time is shortened without impairment of the aesthetic appearance of the front panel due to unsightly cut marks left by the trimming of the residual sprue resin remaining in the pin-point gates.

Abstract: A method and apparatus for placement of labels within the blow molds of an injection blow molding machine. The injection blow molding machine comprising a turret having plurality of circumferentially spaced surfaces, each of which supports a plurality of spaced core rods, a plurality of injection molds at an injection molding station for forming a plurality of preforms, and a plurality of blow mold sections at a blow molding station which close about the preforms so that the preforms can be blown outwardly against the confines of the mold to form hollow plastic articles. The blow molds include movable bases exposing the interior of the blow molds when the blow molds are closed about preforms on the core rods.

Abstract: An apparatus for handling and transferring an article formed in an injection molding machine includes a pair of spaced tracks. Inner ends of these tracks are positioned below a mold carried by the machine with the tracks positioned transversely to opening and closing movement of the mold by the machine. On these tracks is a slideable basket which may be moved from the track inner end to an outer end away from the machine. The basket is operatively connected to a pneumatic drive operated by a controller. During forming of the article, the basket moves under the mold. When forming is complete, the mold opens and the article ejected. The article falls into the basket which has a cushioney surface to inhibit damage. Opening of the mold is sensed by the controller to activate the pneumatic drive and move the basket and article to the track outer end where the article is removed. Concurrently the mold closes to begin a further forming cycle.

Abstract: For manufacturing articles of plastics, rubber or any other material a mold or die assembly comprising a mold or die base assembled from repetitive modular standard elements consisting of substantially "ready to use" interchangeable base plates is provided by the invention.The base plates are prefabricated by high-precision castings or galvanoplastics or any other similar high-precisious non-cutting method of manufacture.At least two of such base plates are, as mold or die plates, provided with a pre-determined number and arrangement of finished to sized, prefabricated cylindrical bores or piercings of any non-circular, mainly polygonal cross-section. Each of said bores or piercings is capable of fittingly receiving an interchangeable mold or die insert carrying the individually designed (negative) mold or die cavity surface for forming the particular article(s) to be manufactured.

Abstract: There is provided an apparatus for the manufacture of plastic parts from thermoplastic, thermoset and/or elastomer material by injection molding or reaction injection molding. The apparatus includes a multi-station locking unit of horizontal or vertical configuration adapted to hold a number of molds, and an associated injection unit for the simultaneous injection of the molds. The apparatus further has a movable center mold clamping plate sectioned lengthwise relative to the locking direction, the two parts of the plate being kept together by a high-speed clamping device and having arranged between the parts a melt conduction system having one or a number of separate melt conduction rails. Each melt conduction rail is rigidly clamped at its face between the sectioned mold clamping plate lengthwise relative to the direction of flow of the melt.

Abstract: The invention relates to an injection molding machine for the manufacture of plastic parts from thermoplastic, thermoset and/or elastomer material by injection molding or reaction injection molding. The machine includes a multi-station locking unit of horizontal or vertical configuration designed to hold a number of molds and an associated injection unit for the simultaneous injection of the molds. The apparatus further includes two outer mold clamping plates, one of which is arranged on guide elements and movable thereon in the locking direction, and a center mold-holding part movably arranged on guide elements between the two mold clamping plates. The mold-holding part is provided with a heatable melt conduction system with sprue nozzles and has one half of a mold attached to each of its two sides. The center mold-holding part is designed as a mold clamping plate sectioned lengthwise in three parts relative to the locking direction.

Abstract: A sports shoe such as a soccer shoe having an injection molded sole molded to an inner sole, the sole having open spaces and injection molded cleats molded to the inner sole.

Abstract: This invention relates to a multi-cavity injection molding system in which a number of nozzles are fixed to a common manifold, and valve gating is provided by actuating the manifold and the nozzles together. A pair of hydraulically actuated pistons are mounted to drive the manifold and nozzles between a retracted open position and a forward closed position. Each nozzle has a truncated tip on the forward end portion which seats in a gate in the closed position. Pressurized melt flows through a melt passage which branches in the manifold and extends through each nozzle to a melt receiving space around the forward end portion. A circumferential sealing and locating flange prevents the leakage of melt from this space as the nozzle reciprocates.

Abstract: A mold for transfer molding having a cavity block in which a mold injected with resin is formed and a templet for holding the cavity block, in which a liquid layer is provided between the templet and a support member for supporting the templet, whereby the templet can be moved up and down on the liquid layer at its respective portions.

Abstract: A molding apparatus and method for producing a thermoplastic lens having a minimum of stress including a male mold and a female mold defining therebetween a molding space, one of the molds being mounted for movement towards and away from the other mold, and a gate mounted adjacent to the other mold for the passage of thermoplastic resin. The other mold defines a window width for admitting thermoplastic resin to the molding space. A compression pressure applying member such as a wedge-shaped slide member is further provided for moving the other mold toward and away from the one mold so as to compress thermoplastic resin within the molding space as well as to automatically withdraw the other mold from the one mold prior to the injection of thermoplastic resin.

Abstract: The cell poles of an electric battery, which have already been cast on a fully assembled plate group which is fixed in proper position for mounting in a holding box, are provided with a plastic coating using a dual injection mold which matches the predetermined distance between the poles. After the two mold halves are closed over the poles, a plastic melt is injected into cavities corresponding to the poles, which plastic is at the same time prevented from escaping from the mold by a gasket at the base of each cell pole, and a movable slide at the forwardmost end of each cell pole.

Abstract: In a conventional multiplunger transfer molding die apparatus having plungers for pressurizing molding material put in plural material supply pots formed in each mated surface of upper and lower chase blocks, when the pitch of the material supply pots is required to change, the whole die apparatus has been exchanged, thus a complicated adjustment work of the plunger pitch, a broad die storage space, an uneconomical die apparatus preparation being required. To overcome these problems, only the upper and lower chase blocks are exchanged and the pitch of plungers is adjusted according to the replaced chase blocks by means of locating means.

Abstract: This invention relates to an improved manifold system for a multi-cavity injection molding system. The manifold system has one elongated bridging manifold which extends transversely across a number of spaced elongated support manifolds. Each of the support manifolds, in turn, extend across a number of heated probes or nozzles, each of which leads to a gate to a cavity. The bridging manifold has a portion of the hot runner passage extending through it from a single inlet to receive melt from the molding machine to a number of spaced outlets. Each of the support manifolds also has an inlet which is in alignment with one of the outlets from the bridging manifold and a number of spaced outlets. Each of the outlets of the support manifolds is in alignment with an inlet to one of the probes or nozzles. Each of the manifold has two way junctions at which a larger diameter portion of the hot runner passage joins two smaller diameter downstream portions.

Abstract: An instrument (22 and 23) for removing irritating particles from the eye, for instance, consists of a tubular rod provided at one end with a flexible eye or loop clamped therein. The object of the invention is to simplify manufacture of such an instrument by supplying liquid plastic to a moulding tool (1), both rod (22) and eye or loop (23) being formed as a single, coherent unit.

Abstract: A compression molding apparatus comprising a rotary compression molding means, a material feed means and an article carrying means.

Abstract: An injection molding apparatus for the manufacture of plastic parts from thermoplastic, duroplastic and/or elastomer material by injection molding or reaction injection molding is provided. The apparatus has a multi-station locking unit of horizontal or vertical design adapted to receive a plurality of molds, an injection unit associated therewith for the simultaneous injection of the molds, two outer mold-clamping plates one of which is movably arranged on guide elements for moving in the locking direction, and a centrally disposed mold-receiving part movably arranged on guide elements between the two mold-clamping plates. The mold-receiving part is provided with a heatable melt-guiding system with sprue nozzles and has fastened to each of its two sides one half of a mold. The centrally disposed mold-receiving part is a mold-clamping plate divided crosswise relative to the locking direction, wherein the two parts are kept together by a high-speed clamping device.

Abstract: There is provided an apparatus for the manufacture of plastic parts from thermoplastic, thermoset and/or elastomer material by injection molding or reaction injection molding. The apparatus includes a multi-station locking unit of horizontal or vertical configuration adapted to hold a number of molds, and an associated injection unit of the simultaneous injection of the molds. The apparatus further has a movable center mold clamping plate sectioned lengthwise relative to the locking direction, the two parts of the plate being kept together by a high-speed clamping device and having arranged between the parts a melt conduction system having one or a number of separate melt conduction rails. Each melt conduction rail is rigidly clamped at its face between the sectioned mold clamping plate lengthwise relative to the direction of flow of the melt.

Abstract: In an injection resin machine, runners are provided perpendicular to the runners of the fixed plate in order to force the resin flow toward the sprues into a same direction and to achieve uniform resin pressure in the proceeding direction, thus realizing uniform injection into the runners.

Abstract: An apparatus is disclosed for encapsulating a plurality of electronic components, which are bonded to the conductors of a strip, within a mold. The apparatus has an injection unit made up of a plurality of plungers slidable in a carrier and controlled by hydraulic cylinders. The hydraulic cylinders apply pressure to the plungers, which have a heating element for heating the material to be injected. A sensor attached to each plunger senses when the material is sufficiently softened, at which point a driving mechanism drives the entire carrier toward the mold, causing the plungers to inject the material into the mold.

Abstract: A molder for molding double-layered preforms in an injection, stretching and blow molding machine wherein a plurality of neck molds which also serve as a member for holding preforms and molded articles are mounted at given intervals on the undersurface of a transferring platen provided above a machine base and which is intermittently rotated so that the neck molds can be opened and closed, and devices required from injection molding of preforms to stretching and blow molding are disposed at stopping positions of said neck molds.

Abstract: An improved mold for injection molding suction cups is disclosed. Conventionally, plastic is injected through a runner into a mold cavity defined by at least two mold sections having mating faces which can be moved apart to open the mold cavity and the cavity is shaped to define a suction cup having a head and a cup shaped body which body has an outer circumferential edge between its top surface and its bottom surface. The improved mold creates a wedge-shaped tab during molding of the suction cup. The thin part of the tab is adjacent to the outer circumference of the suction cup, One fills the mold cavity by injecting plastic through a gate which is adjacent to the thick part of the tab, said gate having an opening not larger than one half the thickness of the tab, said opening positioned so as not to intersect a face of the mold section.

Abstract: An injection molding machine for plastics and any other similar materials. This invention molding machine is provided with a plasticization device for exclusive use which consecutively plasticizes material and feeds plasticized material to a plurality of injection devices in regular sequence. Each of the injection devices has its corresponding mold clamping device. By virtue of this construction, working efficiency of main sections of the machine is increased, resulting in a higher productivity of the entire injection molding machine.

Abstract: A plastic injection mold having means therein for holding an insert to be secured in the formed product. A pair of complimentary sized mold sections are movable together, one mold section having a pin fixedly mounted thereto and extending toward a second pin slidably mounted in the second mold section and aligned with the first pin. In the preferred embodiment, a helical spring contacting the slidable pin urges the pin outwardly to initially hold an insert. As the mold closes, the pins are contacted together with the spring being yieldable to allow retraction of one pin and the transfer of the insert mounted thereon onto the second pin. In an alternate embodiment, the retractable pin is fixedly mounted to a movable plate having a spring loaded leg depending therefrom with the leg being contactable by the mold sections as the mold is closed for the retraction of the slidable pin and the transfer of the insert.

Abstract: In a hot-runner plastic injection system, part of a resin passage connecting the nozzle of an injection molding machine and cavities of a mold adjacent to each of the cavities is formed of a tubular member of material which can be heated by high frequency induction heating. High frequency induction heating windings are wound around the tubular members and are connected to a high frequency power source in series with each other. There is provided a temperature controller for controlling the temperature of the tubular members by controlling the power to be supplied to the heating windings.

Abstract: In a small-sized and precision injection molding apparatus, a raw material supply means, a raw material plasticization means, an injection plunger means and a melted resin flow passage means are all together incorporated in a mold, thereby a substantial distance from the raw material up to a cavity becomes shorter. Thus, an overall construction of the injection molding apparatus becomes small-size and compact.

Abstract: A device for moulding soles composed of a rubber tread and a polyurethane intermediate layer and for directly attaching the soles to shoe shafts includes a bottom work station in which the rubber tread is moulded, a top moulding station in which the polyurethane intermediate layer is moulded between the rubber tread and a shoe shaft, and an intermediate cooling station wherein the rubber tread is cooled prior to being transported to the top moulding station.

Abstract: An apparatus for molding three concentric plastic materials into a composite body in which the mold includes a pair of molding blocks having reduced ends which define an inner cylindrical cavity into which a first material may be injected, a pair of tubular molding sleeves surrounding the molding blocks and axially movable relative thereto which define an intermediate cavity therebetween into which a second material may be selectively injected to form a second intermediate concentric portion of a composite body and a fixed molding cavity with which the inner and intermediate molding cavities are selectively aligned so that a third material may be selectively injected to form an outer concentric portion of the composite body.

Abstract: This invention relates to an improved valve pin bushing for a multi-cavity, injection molding system. The valve pin bushing has a central bore through which the valve pin extends. The melt duct extends through the bushing to join an enlarged portion of the central bore around the valve pin. In the bushing according to the invention, the melt duct branches into two arms with smoothly curved bends which lead to opposite sides of the valve pin. This avoids the problem of streaking and slow melt flow on the opposite side of the valve pin.

Abstract: A improved mold, apparatus and method for injection molding is provided. The apparatus is of the type which includes a means for opening and closing a multi-part injection molding mold, means for supplying molten material under high pressure into the mold cavity when the mold is closed and means for removing articles molded in the cavity on cooling. The improvement is provided by a new multi-part mold which is made up of at least two parts. Each part of the mold comprises a mold block portion having a ceramic mold cavity insert. The ceramic mold cavity inserts define the walls of the mold cavity when the mold is closed. Each mold cavity insert comprises a shaped ceramic body having a mounting surface adapted to fit under compressive stress throughout the entire molding operation within a mounting cavity of the mold block portion.

Abstract: An injection mold is described for producing the housings of integrated circuits. The injection mold icludes a first mold half (30) in which are disposed a number of mold recesses (46) corresponding to the number of housings to be made simultaneously, having a depth corresponding to a portion of the height of the housings, and supply passages (48, 50, 52, 54, 56, 58) leading to the mold recesses (46). In a second mold half (32) which is adapted to be brought in the closure direction into engagement with the first mold half (30) a number of mold recesses (76) equal to the number in the first mold half (30) are disposed in corresponding arrangement, the depth thereof being equal to the remaining portion of the height of the housings to be made. The mold recesses (46) in one of the mold halves (32) are disposed groupwise in mold portions (64) which are held in the one mold half (32) displaceably in the closure and opening direction.

Abstract: This invention relates to hydraulic actuating mechanism for a valve gated injection molding system wherein the enlarged head of the valve pin is removably connected to the piston and a floating seal is provided against the leakage of hydraulic fluid. The actuating mechanism has a piston which is reciprocated in a cylinder between open and closed positions. The valve pin extends through a bore in the piston and has an enlarged head which is retained in a cup in the piston by a circular cap which fits over it. The cap is held in position between a removable resilient retaining ring which snaps into a groove and a compressible O-ring. Thus, both a seal against leakage and an easily releasable connection between the valve pin and the piston are provided by the combination of the resilient retaining ring and the O-ring.

Abstract: An injection nozzle assembly is used for molding a plurality of articles having accurate dimensions without causing a sink mark to appear in the molded article. The injection nozzle assembly comprises a body which is heated to a temperature higher than the melting point of thermoplastic material. A cylindrical bore is formed within the body, and an outlet port is formed at one end of said cylindrical bore. A plunger moves within the cylindrical bore between a first position near the outlet port to a second position which is remote from the outlet port. A first feed line supplies the molten thermoplastic material and a second feed line feeds high pressure through passageways that are formed within the body. The plunger is formed within a first passageway connecting the feed line with the outlet port when the plunger is moved to the second position. The pressure at the outlet port is reduced by the movement of the plunger from the first position to the second position.

Abstract: An adjustable molding apparatus for injection molding interfacing plastic components wherein the mold includes three sliding blocks of which the outermost blocks are concurrently moved relative to the middle block which is shiftable between various positions relative to the outermost blocks so as to alternatively form two molding cavities for receiving plastic materials so that the materials may be molded in intimate facing relationship with one another.

Abstract: A telescoped assembly of sleeves for supporting, sealing and insulating a floating manifold between mold plates or other abutments in an injection molding machine.

Abstract: The injection nozzle has a central heating rod (1) and jacket components (2 and 3), with the heating rod connected at the upper end with one (3) of the jacket components and at the lower end, through a fork (8), with the other (2). The jacket components are electrically insulated from each other by disks (4 and 5) and demarcate an annular channel (15) for the plastic to flow through. The plastic is introduced into the channel at the top and through exits (14) at the bottom into the supply aperture of an injection mold. The nozzle has two points (11) at the bottom, each extending into or into the vicinity of one supply aperture to a mold cavity. Two mold cavities can accordingly be simultaneously filled with plastic by one injection nozzle.

Abstract: This invention relates to an injection molding system in which melt flows in channels in the outer surface of a heated probe seated in the cavity plate on its way to the gate leading to the cavity. The probe has a tip end in alignment with the gate and the probe is reciprocated between open and closed positions to valve gate the flow of melt to the cavity. According to a preferred embodiment, in a multi-cavity system a number of probes are fixed to a manifold which is actuated to valve gate all of the cavities simultaneously. Hydraulic cylinders are provided to drive the manifold to the closed position, and injection melt pressure acting on the tip ends of the probes is utilized to return them to the open position. Valve gating the heated probes provides the advantage of improved temperature control of the melt in the immediate gate area.

Abstract: Method and apparatus for molding a plurality of lenses of thermoplastic resin of different optical power and/or mass that comprises a plurality of molding stations, each including a rigidly supported male mold and a female mold allowed to float freely within defined limits. At each molding station, a wedge-shaped slide member whose position is controlled by a hydraulic piston is movable an independent distance over the female mold between a home position allowing maximum free floating and an operative position independent for each slide member to transfer a compression force onto an injected body of molten resin at said station. The hydraulic pistons are actuated from a common manifold to allow equal compression pressure at each molding station after the slide members move their independent distances.

Abstract: The invention relates to a method for the manufacture of tubular preforms. Its purpose is to improve the flow pattern in the plastics chamber and simultaneously to shorten the dwell time of the plastics. This is achieved, in the course of the dip blow method, by the fact that the geometric form of a plastics chamber (that is distinct from a separate screw chamber) is changed and the volume is decreased so that the tubular preform acquires a certain thickness or thickness distribution.

Abstract: An injection molding machine includes a platen having a plurality of regularly spaced mold element-receiving chambers adapted to receive any of a number of various mold elements substantially wholly within the stationary platen. A hot manifold system is included between the stationary platen and a plastics injector unit, which includes a plurality of blocks independently coupled to the fixed platen, each block having channels through which the plastics material can flow, the channels of adjacent blocks being coupled by a coupling unit. The machine is particularly designed for quick inexpensive mold changes, and has particular utility in laboratory testing of mold designs and small low-capacity production in satellite plants.

Abstract: A press with a plurality of injection plungers, which can be used to enclose integrated circuits in plastics packages, is provided with additional compensating pistons. The lower ends of the compensating pistons and the upper ends of the injection plungers project into a filling pot in which the plastics material is molded. The injection plungers force the plastics material in the injection mold through channels into cavities provided in the mold. When a predetermined pressure P.sub.k is exceeded, the compensating pistons retreat, so that a pressure drop and, thus, pressure limitation occur. In this manner, scrap would be avoided even if too large a quantity of plastics material were placed in the filling pot.

Abstract: A mold for making a bucket having a pivoted handle. The mold has cooperating mold parts defining cavities for molding a bucket and slotted bail retention means. The mold parts are movable only linearly to release the molded product.

Abstract: In order to mold a plurality of articles (20--20) which are disposed in a line, a molding arrangement in an apparatus (60) includes a plurality of cavities (109--109) which are spaced equidistantly from an infeed sprue (131). A primary network of a distribution system (50) through which an injection molding material is flowed from the infeed sprue to cavity gates (151--151) is disposed substantially along a vertical plane (150). Afterwards the injection molding material which has been flowed from the primary network and along a secondary network into the cavities is solidified. Then the primary network is exposed by causing wedge blocks (79--79) to be disengaged from each other and from an adjacent stationary platen (62) and cavity plate (90) by movement of each block in a direction transverse to the plane.

Abstract: This invention relates to an improved method of manufacturing injection molding manifolds for multicavity molding. The method includes gun drilling a longitudinal duct through a steel manifold body, drilling a transverse inlet duct to connect to an inlet on one surface of the manifold, and drilling diagonal outlet ducts to connect to spaced outlets on the opposite surface of the manifold. The outlet ducts are smaller in diameter than the longitudinal duct to match the rest of the system. Before the outlet ducts are drilled, end portions of the longitudinal duct are drilled out to a larger diameter and steel plugs having a tapered well are securely welded into them with the mouth of the well in alignment with the longitudinal duct. The plugs are larger in diameter than the central portion of the longitudinal duct to avoid the formation of thin knife edge portions where the outlet ducts join the longitudinal duct which often break down during use.

Abstract: A mold assembly for producing a plastic container having internal compartments separated by partitions. A male mold is slidably moveable into a female mold and includes a plurality of upstanding cores to form the container with injectors provided to force plastic melt between the molds and between the cores. A plurality of side locking members are reciprocably mounted in the cores and when extended contact adjacent cores limiting relative motion therebetween. The locking members form holes in the partitions formed between the cores. The locking members are withdrawn only after the plastic melt is cooled.

Abstract: Apparatus for forming objects from molten material includes a mold frame and a movable mold side having complementary faces that define molding cavities. The mold frame includes a mold housing having an internally heated manifold which has a plastic distribution channel for feeding plastic to an injection nozzle passageway having a restricted discharge nozzle that discharges the plastic into a molding cavity. Within the injection nozzle passageway is a heater probe which has an internal heater, preferably an electrical cartridge heater. The probe is secured by an integral seating flange to the mold housing to hold the probe coaxially aligned in the injection nozzle passageway and to hold the probe against shifting with thermal expansion and contraction of the manifold.

Abstract: A mold structure having at least first, second and third mold parts stacked one on top of the other, each having structure thereon defining at least one part of a mold cavity. The second part is oriented between the first and third parts and has mold cavities on both sides thereof. A support structure is provided for supporting the first mold part for movement toward and away from the third mold part. Structure is included within the mold structure to limit the spacing between the first and second mold parts to a prescribed spacing so that as the first mold part is moved away from the third mold part, the second mold part will be spaced a prescribed distance away from both the first and third mold parts.The invention also includes a mold opening structure which is coaxially aligned with the elongate tie rod extending between the mold parts. This structure further effects a safe and positive opening of the mold structure.

Abstract: Apparatus for forming a concave lens of resin material and adapted to be used, for example, in spectacles, video projection devices, etc., whereby raw material is fed into substantially the center thinner portion of the mold first and then radially outwardly until the material reaches the periphery, thereby to eliminate weld lines in the produced lenses.