Abstract: A gate portion constituting a gate of a resin molding die is made of a hard alloy having a hardness greater than the predetermined hardness in the iron-based hard alloy used to from a cavity block and a center block. Opposing surfaces of the cavity block halves include a silicone rubber layer at least at the portions thereof which contact portions of the lead frame in a semiconductor encapsulation molding apparatus.

Abstract: Real time distance and pressure data of a plunger (35) relative to a mold compound is provided by a compensation assembly (29) in a mold press (10). The compensation assembly has a sliding block assembly (30) which moves substantially in the same direction as the plungers (35). The sliding block assembly (30) has pressure control cylinders (33) which limit the pressure plungers (35) can apply. If the pressure on the plungers (35) should exceed this limit, the plungers (35) retract towards the sliding block assembly (30). A sensor (37) is coupled between the sliding block assembly (30) and the plungers (35) to measure the distance the plungers have moved towards the sliding block assembly (30). In one application, the sensor (37) is formed from a linear voltage displacement transducer (LVDT) so the mold press (10) can have real time pressure and distance data.

Abstract: In an apparatus for molding resin to seal electronic parts, an internal die space defined at least by pots, cull portions, resin passages and cavities when an upper mold section and a lower mold section are closed, is cut off or sealed from the exterior atmosphere. Thereupon the die space is evacuated using a first evacuation by a vacuum source and a second or instantaneous evacuation by an instantaneous evacuation mechanism. The vacuum source for the first evacuation may be an active vacuum pump, while the instantaneous evacuation mechanism may be a vacuum tank that has been previously pumped down, for example. Using this apparatus, it is possible to quickly improve the degree of vacuum in the internal die space by efficiently and reliably discharging air, moisture and gas from the internal die space to the exterior due to a synergistic action of the evacuation and the instantaneous evacuation. Consequently, the formation of voids in resin molded members is prevented.

Abstract: A printed wiring board with either a pin grid array, a ball grid array, a land grid array, etc. of electrical contacts is prepared with a heat sink attached in the usual manner. A passage is provided either in the printed wiring board or in the heat sink so that during the transfer molding process, fluid molding compound passes latitudinally under the heat sink into a cavity below the heat sink. The mold is provided with a biased plug that exerts pressure on the heat sink or printed wiring board to prevent molding compound from covering the heat sink. The biased plug also accommodates variations in the thickness of the printed wiring board.

Abstract: There is provided a mold die set for molding a package body which is composed of a lead frame and a semiconductor chip mounted on the lead frame, and the lead frame has a hole. The mold die set is composed of an upper mold die and a lower mold die and the package body being clamped by the upper mold die and the lower mold die. The lower mold die includes a runner section, a table section connected to the runner section and protruding from a bottom of the runner section, a lower concave section connected to the table section, and a lower gate disposed between the table section and the lower concave section.

Abstract: It is generally known that the most common reason for replacing rotary electric machines is failure of field windings. Vibrations and primary overheating of field windings is the main reason for motor and generator repair. Consequently field windings have been fan cooled, externally ventilated, and totally enclosed. To solve this failure problem stators have been completely encapsulated, drip coated, and entirely coated. But all of these procedures are subject to certain disadvantages. The method and apparatus herein overcome such disadvantages. The apparatus includes structural members for embedding in a solid material field windings of stators of rotary electric machines in order to insulate and cool electric machines in which the stators are employed.

Abstract: An automated transfer/injection process is defined that includes a charge forming unit, a shuttle unit, and a molding unit. The charge is formed from one or more slabs of reinforcing fibers and a resinous material. Once formed, the charge is preheated in the charge shuttle unit and is delivered to the molding unit, whereupon the preheated charges are forced by the pressure of a movable platform under vacuum into a mold cavity for polymerization. The fibers within the slabs are randomly oriented in parallel horizontal planes such that they are always parallel to the direction of initial flow into the cavity.

Abstract: A fixture for fixing an annular upper air isolation member which is provided around an outer side of an upper mold section to an upper mounting plate is released, thereby rotating the air isolation member by a rotational member and fixing the same by a rotational position regulating member. An upper chase unit is exchanged through an upper opening which is defined by the upper mounting plate and the rotated air isolation member. A lower chase unit is also exchanged in a similar manner. Due to this structure, a sealing mechanism for a resin sealing/molding apparatus for electronic parts which can readily and quickly exchange a mold in response to small lot production of various types of products is provided.

Abstract: An automatic plunger apparatus and method therefor is disclosed for compressing molten plastic into a cavity for forming an encapsulated semiconductor device. A compressing device drives a plunger member in order to compress and direct molten plastic to flow in a forward direction into the cavity. An overload compensator is coupled to the plunger member for permitting the plunger member to withdraw in a reverse direction when the plunger member is prevented from compressing and directing the molten plastic to flow in the forward direction into the cavity. The overload compensator comprises a first member retained within a second member for transferring the force from the compressing device into motion of the plunger member.

Abstract: A gate portion constituting a gate of a resin molding die is made of a hard alloy having a hardness greater than the predetermined hardness in the iron-based hard alloy used to form a cavity block and a center block. Opposing surfaces of the cavity block halves include a polytetrafluoroethylene layer at least at the portions thereof which contact portions of the lead frame in a semiconductor encapsulation molding apparatus.

Abstract: A molding die for sealing a semiconductor element with a resin includes an upper and a lower mold half. A leadframe having a resin passage aperture is sandwiched between the lower mold half and the upper mold half. The lower mold half has a lower runner space, a lower cavity, and a lower gate provided between the lower runner space and the lower cavity. The upper mold half has an upper resin well, an upper cavity, and an upper gate provided between the resin well and the upper cavity. The length of the upper resin well in the direction of the flow of resin is equal to or greater than the distance from the lower gate to the front edge of a lower runner rising slope, to thereby obtain a final product which is free from resin burrs formed in the upper resin well.

Abstract: A plunger (22), used in a standard mold, has a vent seal device (23) and spring (24) that evacuates air through an exhaust port 26a, and channels 26 and 26b from the mold prior to moving the mold compound into the runner 27.

Abstract: A printed wiring board with either a pin grid array, a ball grid array, a land grid array, etc. of electrical contacts is prepared with a heat sink attached in the usual manner. A passage is provided either in the printed wiring board or in the heat sink so that during the transfer molding process, fluid molding compound passes latitudinally under the heat sink into a cavity below the heat sink. The mold is provided with a biased plug that exerts pressure on the heat sink or printed wiring board to prevent molding compound from covering the heat sink. The biased plug also accommodates variations in the thickness of the printed wiring board.

Abstract: A direct drive electro-mechanical press for encapsulating semiconductor devices has at least a clamping axis and a transfer axis. The clamping axis has a planetary roller screw coupled to a tie bar platen assembly on which at least one top mold is mounted. A two-speed gearbox is further coupled to the clamping axis for switching between a high speed mode and a high torque mode along the clamping axis. The two-speed gearbox has a high speed clutch coupled to a speed reducer and a high torque clutch respectively. The transfer axis is slidably located above the clamping axis; the transfer axis has another planetary roller screw coupled to a bottom platen on which at least one bottom mold is mounted. The transfer axis transfers the molding resin from the pot into the cavities formed when the top and bottom molds are clamped together.

Abstract: A plunger (22), used in a standard mold, has a movable piston (23) and spring (24) that reduce the cull space when piston (23) is pressed downward into the cull mold compound.

Abstract: In an apparatus for resin transfer molding, the resin is introduced into a heated resin pot, and a piston member is driven through the resin pot to displace the resin into a heated resin line. The temperature of the resin in the resin pot is substantially constant, and is above room temperature but below the catalyzing temperature of the resin. The preheated resin flows from the resin line into a preheater, which heats the resin to molding temperature and catalyzes the resin, and the catalyzed resin is then introduced into the mold cavity of a resin transfer mold containing a structural preform. The resin is maintained at a substantially constant pressure within the heated resin line, and the movement of the piston member is continuously monitored during the resin transfer process. The resin transfer process is terminated when the rate of movement of the piston member decreases below a predetermined minimum value approaching zero.

Abstract: A mold for a semiconductor package having a port for feeding resin which can be fixed either in an upper mold (1) or a bottom mold (2) corresponding to the location of the flange tip so that the operating rate of the equipment is increased to achieve high productivity.

Abstract: An improved transfer molding apparatus is provided for molding a preheated resin under pressure to thereby encapsulate a small element, such as a semiconductor device or package. In one aspect of the invention, the improvement consists of providing a shortened pot into which a piston is forcibly pressed to generate a flow of preheated resin in the encapsulating process, the improvement comprising the replacement of a single-element top drive plate, as found in a conventional apparatus, by a two-piece top drive plate which enables a shortening of the pot and corresponding reduction in the amount of air that would otherwise be trapped between the plunger and the resin during the process. The elimination of this air significantly reduces foaming, porosity, voids, and other defects in the cured resin which finally surrounds the electrical elements encapsulated thereby.

Abstract: A twin-piston food pump includes a hydraulic cylinder coupled with each piston for driving the pistons and a linear transducer coupled with each cylinder for determining the positions thereof. Control circuitry coupled with the transducers determines the velocity of the cylinders and thereby the pistons and controls the application of hydraulic fluid through the cylinders to maintain a constant food product flow rate.

Abstract: An improved plunger apparatus used in a resin molding device for encapsulating electronic components. At least one annular recess is located in the bottom side of the plunger. The annular recess redirects the plasticized resin to flow towards the mold cavities in the molding device and away from the interface between the plunger and the cylinder of the molding device, thereby optimizing the flow of resin to the cavities and reducing the tendency of excess gas and resin to flow away from the cavities. At least one flat side is located in the lengthwise surface of the plunger. The flat side forms an enlarged clearance in the interface between the flat side and the cylinder of the molding device. The enlarged clearance receives and provides an outlet for any excess gas or resin that flows in the interface. The improved plunger still stably guides within the cylinder, and the improved plunger allows the molding apparatus to encapsulate electronic components more economically, efficiently, and effectively.

Abstract: An apparatus for encapsulating with plastic lead frames having chips arranged thereon includes mutually movable mold halves (102, 103). In the closed position a mold cavity is bounded, in which molding material is arranged under pressure via a runner. the pressure is provided by a plunger-cylinder (134-133) which carries up the molding material. Leaking molding material can result in adhering of the plunger to the cylinder wall, which is prevented according to the invention in that the outer wall of the plunger (134) is provided with scraping edges which scrape clean the inner wall of the cylinder (133) during operation.

Abstract: Method for pressing a plastic (6), which cures by means of a reaction, from a displacement chamber (4) via at least one injection channel (3) and a gate (2) to a mould cavity (1), said method at least comprising the following steps: pressurising the plastic (6) with an amount of a pressing auxiliary (7) in the displacement chamber (4); pressing the plastic (6) into the mould cavity (1); and allowing the plastic to cure under pressure in the mould cavity, the pressing auxiliary (7) being plastically deformable under the conditions of pressing and the amount thereof being sufficient to be pressed to the vicinity of the gate (2) of the mould cavity (1). Preferably the pressing auxiliary (7) is a thermoplastic.

Abstract: Encapsulation molding equipment includes individual mold bases each having an elongated shallow recess which receives strip-like carriers supporting semi-conductor chips and like objects for encapsulation. Cavity inserts having various numbers of cavities of different size and dimension individual to carriers having like numbers of chips of a range of size and dimension fit over the strips with each cavity on an insert surrounding the chip to be encapsulated. Gate and vent passages are formed on the surface of the insert spaced away from the mold base member for supply of resin from a central resin receptacle. Gate passages in the cavity inserts are configured to provide a restriction at the edge of each mold cavity, thereby accelerating the flow of liquid resin, rapidly filling the cavities and avoiding the entrapment of gas bubbles. The inserts have mold vent passages which allow for rapid venting of displaced gases from the cavities.

Abstract: The invention relates to an apparatus for injection molding the shells of a mini-disk cartridge or the like. More particularly, the device includes a main cavity having a shape of mini-disk shell. The mold contains various projections and indentations on the first and second surfaces, respectively, which are adapted to form a shutter recess near a first edge of the lower shell, a read/write port for a media disk in a vicinity of the first edge within the shutter recess, a shutter guide track on the outer surface of the lower shell close to and parallel to the first edge, a drive port for rotating a media disk, and various fastening bosses for fastening the upper and lower shells of the mini-disk cartridge together. A single hot-runner valve gate is placed in the mold close to one corner such that small cavities within the cavity are filled with polymer melt first.

Abstract: A gas spring (602) is used as a buffer device in a resin-sealing apparatus for applying a compressive force to a plunger (15). In the gas spring (602), the compressive force at which a compression displacement starts is easily established as required, and the increasing degree of the compressive force with increasing compression displacement is established slowly without difficulty. Any errors in applying resin injection pressures to a plurality of plungers, due to variations in the amount of resin of tablets and in length of plungers, are absorbed in a wide range of the compression displacements thereof so that the resin injection pressures in practice are substantially equalized.

Abstract: Encapsulation molding equipment includes individual loading bars each having an elongated support surface which receives strip-like carriers supporting semi-conductor chips and like objects for encapsulation. Cavity inserts having plural rows of cavities of different size and dimension individual to carriers having like numbers of chips of a range of size and dimension fit over the strips with each cavity on an insert surrounding the chip to be encapsulated. Converging gate passages and vent passages are formed on the surface of the insert spaced away from the mold base member for supply of resin from a central resin receptacle to the cavities. Support of the cavity inserts independent of the loading bars and resilient mounting of the loading bars is disclosed. The mold is completed by an upper mold member which closes the mold and effects a seal between the mold parts and provides for delivery of encapsulating resin to the cavities in the cavity inserts.

Abstract: A molding machine includes a mold composed of lower and upper mold sections. A recess is defined in the lower mold section to receive a lead frame or other objects. The lead frame is sandwiched between the upper and lower mold sections. A mold cavity is defined in the lower mold section below the recess so as to receive a thermosetting resin or encapsulant. A gasket groove is defined adjacent to the mold cavity to receive a gasket. The gasket is subject to plastic deformation upon application of force. An oil chamber is communicated with the gasket groove and contains hydraulic oil. The hydraulic oil is pressurized to urge the gasket against the lead frame. As a result, the gasket is so deformed as to closely contact the surface of the lead frame and seal the mold cavity. The hydraulic oil is preferably mixed with thermoplastic resin in powder form.

Abstract: In the device for pre-shaping plasticated plastics material, a mold formed by two plates (5, 6) arranged so as to be stationary and by two rotatably mounted calibrating jaws (3, 4), and two levers (11, 12) with drive devices (15, 16), are arranged between two columns (1, 2) which are arranged in parallel. One of the calibration Jaws (3, 4) in each case is fastened to one end of the levers (11, 12) and one of the drive devices is fastened to their other end.

Abstract: A die-stamped frame is fastened to a heat sink metal baseplate by wedging flexible tabs into receiving indentations of the baseplate while keeping the frame substantially in contact with the surface of the baseplate. The wire welding operations may then take place on the end of the fingers of the patterned metal frame while the same are solidly resting on the surface of the baseplate thus facilitating the welding. The backing-off of the metal frame from the surface of the heat sink baseplate takes place upon the closing of the mold used for encapsulating in resin the device. The injection of the resin and its solidification "freezes" the pins in the backed-off position imposed by the mold upon closing, thus ensuring the electrical isolation between the pins and the integral heat sink baseplate.

Abstract: A metal mold for sealing a semiconductor device with a resin and including a shutter gate mechanism. The mold drives a shutter gate pin by using the ejection stroke of a conventional seal press, and therefore eliminates the need for an extra drive source. It follows that the mold can be implemented only if an existing facility is slightly modified, and it is lower in cost than conventional metal molds.

Abstract: A molding apparatus having variable-volume cavities is provided. The apparatus consists of a lower and an upper mold defining a cavity for the lead frame, and having a conduit for forcing fluid plastic from a reservoir to the cavity for encapsulating an integrated circuit bonded to a lead frame. A pressure source is used to force the plastic from the reservoir through the conduit into both the upper and lower portions of the cavity surrounding the lead frame. The cavity of the mold is equipped with at least one piston-like insert slideably mounted in a bore hole in the surface of the cavity. The insert can be compressed or expanded to reduce or increase, respectively, the volume of the cavity. Thus, the final size of the cavity in the mold is determined by the position of the insert at the end of the encapsulation process. By allowing the expansion of the insert during a first phase of the molding operation, excess plastic is forced into the cavity.

Abstract: Encapsulation molding equipment includes individual mold bases each having an elongated shallow recess which receives strip-like carriers supporting semi-conductor chips and like objects for encapsulation. Cavity inserts having various numbers of cavities of different size and dimension individual to carriers having like numbers of chips of a range of size and dimension fit over the strips with each cavity on an insert surrounding the chip to be encapsulated. Gate and vent passages are formed on the surface of the insert spaced away from the mold base member for supply of resin from a central resin receptacle. The mold is completed by an upper mold insert plate which closes the mold and effects a seal between the mold parts and provides for delivery of encapsulating resin to the cavities in the cavity inserts. Each mold base has a plurality of recesses, each of which receives a carrier strip and a cavity insert.

Abstract: A resin article is made between an outer concave mold part and an inner convex mold part that can fit together so that respective surfaces form a substantially closed mold cavity. This is done by first lining the surface of the outer mold part with a liner sheet and then fitting the lined outer mold part to the inner mold part to form the substantially closed mold cavity. A portion of the surface of the inner mold part is positioned to form a pocket open inward into the cavity and this pocket is filled with a mass of fluent synthetic resin. The surface portion is then pressed inward while the parts are fitted together and without otherwise relatively moving the mold parts to force the resin mass from the pocket into the cavity until the inner-part surface portion lies substantially flush with the rest of the inner-part surface.

Abstract: A mold for resin-packaging electronic components on a pair of leadframes includes an upper mold member and a lower mold member. The mold has two parallel rows of molding cavities, and a row of resin supplying portions arranged between the respective cavity rows. The respective molding cavities have corresponding corner portions formed with injection ports which communicate with the respective resin supplying portions through runners. The respective cavity rows together with the leadframes received in the mold are displaced relative to each other longitudinally thereof by a predetermined amount.

Abstract: An apparatus for molding electronic components. The single-strip molding apparatus has a mold die formed from two mold halves which are movable relative to each other and can be closed upon one another. A leadframe for the component to be molded is placed into a recess in one of the mold halves. Molding material is heated and forced under pressure into the recess containing the leadframe. After the component is molded the mold is opened and the upper half of the mold is cleaned by a combined cleaning-discharge unit. Upon the return stroke of the cleaning-discharge unit, the molded component is removed and the lower half of the mold is cleaned.

Abstract: A resin sealing apparatus includes upper and lower dies each having a chase block with a plurality of cavities into which molten resin is injected and a supporting member for supporting the chase block, the chase blocks of the upper and lower dies being fitted to each other, and a position determining member attached to each of the chase blocks so that the positions of the chase blocks are determined when they are assembled, wherein each of the chase blocks is attached to each of the supporting members so as to be movable in the vertical and lateral directions within given ranges.

Abstract: An apparatus for encapsulating an integrated circuit lead frame in plastic is disclosed. This apparatus includes an upper mold and a lower mold which, when properly joined together, define the package area of the lead frame as well as a reservoir for the molten plastic and a conduit and flow pocket for assuring uniform flow of plastic into the package area of the molds. The integrated circuit lead frame has a flow hole to allow the molten plastic to flow from the conduit into the flow pocket and into the bottom portion of the package area. The conduit also allows the molten plastic to flow directly to the top portion of the package area. With the plastic being more uniformly injected into both (top and bottom) package or cavity areas at once, the likelihood of air pockets, and to overcome wiresweep cavities and other imperfections in the final plastic package is reduced.

Abstract: A mold system for use in resin encapsulation molding includes a cavity serving as a resin molding section in which small size electric elements such as semiconductor devices and electrical parts are encapsulated with a synthetic resin. The system also incudes at least one pot for receiving the synthetic resin material and melting the received synthetic resin material by heating, a cull section communicating with the pot and formed facing to an opening end face, and a conveying passage for communicating the cull section and the cavity to convey molten resin material through the cull section. The synthetic resin material is placed in the cavity and is heated to melt therein, and is extruded out of the pot by a plunger disposed in an axial direction of the pot. The inner bottom of the cull section facing to the opening end face of the pot is formed unevenly.

Abstract: A device for simultaneously encapsulating a number of electronic components is provided with a locking mechanism in which a molding cycle has two phases, i.e. in a first transfer phase, during which plungers for injecting molten resin into encapsulation cavities are locked and driven at a high, controlled speed, followed by a second curing phase, during which the plungers are spring-loaded, unlocked, and stationary, and are subject to the same maximum pressure of the transfer phase. In this way damage to the products is prevented, while the cycle time is reduced and the products obtained have an even and smooth appearance.

Abstract: A molding apparatus for encapsulating devices and having a molding pot wherein the pot has a configured bottom is provided. The configured bottom serves as a shearing force against encapsulating material pellets which are pressed into the configured bottom by a plunger. The shearing force increases the fluidizing action of the pellets thereby lowering the viscosity of the encapsulating material so it easily enters cavities provided in the molding assembly and completely fills the cavities and encapsulates the devices without damage to the devices.

Abstract: A mold for molding a semiconductor package including a semiconductor chip mounted on a lead frame, wherein a major surface of the semiconductor chip is inclined relative to a surface of the semiconductor package, the mold includes a first mold half including a first mold cavity having a first mold surface and at least four first side surfaces, a second mold half including a second mold cavity having a second main surface extending substantially parallel to the first main surface and at least four second side surfaces extending substantially perpendicular to the second main surface, and a portion for supporting the lead frame and the semiconductor chip in the first and second mold cavities and position the major surface of the semiconductor chip in an inclined position relative to the second main surface, wherein the portion for supporting and positioning includes a first mating surface on the first mold half inclined relative to the first main surface and a second mating surface on the second mold half inclin

Abstract: A resin sealing apparatus includes upper and lower dies each having a chase block with a plurality of cavities into which molten resin is injected and a supporting member for supporting the chase block, the chase blocks of the upper and lower dies being fitted to each other, and a position determining member attached to a center block so that the positions of the chase blocks are determined when they are assembled, wherein each of the chase blocks is attached to each of the supporting members so as to be movable in the vertical and lateral directions within given ranges. The center block is provided on the supporting member and is disposed between two of the chase block with center plates interposed therebetween to form an integral unit.

Abstract: A multiple transfer molding die for molding a plurality of semiconductor devices includes a plurality of resin paths between a pot and a plurality of cavities. Each resin path includes a first runner portion whose cross sectional area is determined according to the length between the center of the pot and the end of the first runner portion.

Abstract: Transfer molding equipment, used to encapsulate semiconductor die, is provided with clamps mounted to the mold base to position and align mold chases. Previous designs position and align the top and bottom mold chases using dowels on the mold base received in holes in the chases. The invention reduces the downtime of the mold equipment, and decreases the time required to replace the chases when a different package is to be produced.

Abstract: A resin sealing apparatus that has separable molds having a pot in which resin is injected. The pot communicates with cavities, in which semiconductor chips are set, by runners. The runners lead the resin injected in the pot to the cavities. A recess is provided at the distal end of each runner to hold the resin and air pressed out from the runner.

Abstract: A toy (10) for forming modeling compound includes a base (12), a turntable (16) rotatable on the base, a receptacle (22) on the turntable for receiving the modeling compound, a ram member (34), and a rotary actuator (44) for driving a peripheral drive gear (20) of the turntable to provide screw actuated movement of the ram member for forcing modeling compound from the receptacle (22) through a forming component (32) for forming. In one embodiment, the rotary actuator (44) includes a hand operated crank (74) and in another embodiment is power operated and includes an electric motor (102) and gear drivetrain (108) for providing the screw operated movement of the ram member for the forming. The forming component (32) may be embodied by an extruder (162) or a mold (170) to provide either extrusion or mold forming of the modeling compound.

Abstract: Disclosed is an injection press for use in a transfer molding system for fiber reinforced thermo-setting resins, comprising an injection piston, an injection cylinder in which the injection piston moves, a feed bore which traverses the injection cylinder, a sprue orifice which leads into the mold, a telescoping sleeve which serves to seal off the feed bore when the piston travels toward the sprue orifice, wherein the injection piston seals the transfer bore at the end of the stroke near the sprue orifice, and wherein said feed bore is open when the piston is in a position a stroke length away from the sprue orifice.

Abstract: Apparatus for enclosing semiconductors with resin by molding, including a stationary upper mold having a plurality of pots, and a movable lower mold opposed thereto.The upper and lower molds have cavities to which a resin material supplied to the pots is pressingly injected directly or only through gates.Disposed at the upper mold side is a resin material pressurizing mechanism having plungers fittable into the pots, and one or more cylinders and piston rods for actuating the plungers.

Abstract: An apertured insulation unit is disclosed for interposition between a mold having at least one cavity in which elastomeric stock can be cured in the form of said cavity and an injection unit from which elastomeric stock can be expelled and transferred through the insulation unit to the mold cavity, the mold and injection unit being movable axially relative to one another into and out of pressing association with respective opposite side-faces of the insulation unit. The insulation unit serves to prevent curing of elastomeric stock remaining in the injection unit with the curing of the portion of such stock transferred to the cavity, without separation of either the mold or the injection unit from the insulation unit. The insulation unit is at least in part in the form of a thin, flexible, apertured plate constituted of a thermal-insulatory material which is engageable and forms a parting line with the mold.

Abstract: A process for producing shaped parts from synthetic and similar workable materials by filling molds under pressure, hardening and removing the articles from the molds. Movable, essentially identical mold carriers are provided with article-related mold inserts preselected for the work cycle and locked in place in the carriers. The forming tool is filled with the synthetic, it is exposed for a given time to certain temperature and pressure conditions, the tool is opened and the inserts are expelled. The form carriers are then outfitted with another set of form inserts while the first set of mold inserts are removed from the molding cycle.