Abstract: An improved injection blow molding apparatus. The apparatus includes an injection blow molding machine having work stations and molds. The apparatus includes a process controller for operating the blow molding machine according to a set of processing parameters. Each processing parameter has a respective desired operating range. The apparatus includes a touch screen for inputting signals to the processor for commanding the process controller to adjust the processing parameters. Display software and hardware coupled to the process controller and the touch screen cause the monitor to display respective icons representing each processing parameter. The value of each respective processing parameter is displayed adjacent to the icon. Graphing software generates signals which are transmitted to the monitor. The monitor displays a graph of the selected processing parameter value as a function of time.

Abstract: A method for runnerless injection molding of a synthetic resin, provided with a novel valve gate for performing intermittent temperature control to forcibly change the property of a molten or solidified resin material adjacent to the gate, capable of performing a precision molding operation without leaving an improper gate mark. The apparatus therefor comprises a runner 3 with a temperature maintaining means for storing a molten resin and forming an injection passage, a gate 1 in communication with a cavity 2 connected to the end of the runner 3, a valve pin 4 enclosed within the runner 3, and an intermittent temperature control assembly P.

Abstract: Apparatus for extruding thermoplastic material includes an extruder having inner and outer die lips adjacent an outlet end of the extruder for transporting an annular stream of thermoplastic material therethrough. The outer die lips are divided into a plurality of circumferential sectors. Each sector includes a passage for circulating heated oil for controlling the viscosity of the thermoplastic material being extruded. The temperature and flow of the heated oil flowing through each sector may be varied according to the required thickness of the product being extruded adjacent that sector. A ring-shaped channel carries the heated oil around the die lips for circulation into the individual sectors.

Abstract: A temperature regulating system (preferably a cooling system) for a cyclic processor comprising a mould having at least one internal passageway for receiving temperature regulating fluid, preferably coolant water. Continuous fluid flow will overcool the mould, and so the system normally is set to provide flow only for a part of the cycle, the proportion depending on mould temperature (or of fluid exhaust temperature) from a previous cycle, preferably the immediately preceding cycle and with an averaged temperature over the cycle. Also disclosed is a processor fitted with the system, and a method of controlling the temperature of a fluid cooled processor.

Abstract: A longitudinal stream of cooling air is caused to flow around the cylinder (10) and over the length of each of one or more heating-and-cooling zones. This longitudinal flow is facilitated by specially designed cooling fins (22; 25). The performance of the extruder is improved in that the temperature over the cross-section of the cylinder is more uniform. Moreover, wear and tear on the extrusion screw and on the cylinder are greatly reduced.

Abstract: A temperature control system for a hot nozzle is used in a runner-less molding process of a plastic by an injection molding machine. The control system includes first and second temperature detecting devices for detecting the temperature of the hot nozzle at the front end of the hot nozzle and at a position upstream of the front end, respectively. Control signal outputting units compare the temperature detected by the first and second temperature detecting devices with a first set temperature and a second set temperature, respectively. Based on the temperature differences, first and second control signals corresponding to the temperature differences are calculated and are outputted from the control signal outputting units to a power supply unit which is connected to a power source for regulating the power for heating the hot nozzle.

Abstract: The invention relates to a method of controlling the temperature of an injection mold, in particular for plastics and aluminium diecasting. The molten material being pressure-fed into the mold recess or the mold recesses of an injection mold by means of an extruder or the like in recurring cycles, cured therein, removed from the mold, and pressure-melted material being again supplied with the start of another cycle. A plurality of flow control valves are controlled by a sensor to provide an impulse or intermittent flow of the temperature control medium during each molding cycle at the same point in time as the previous cycle. The sensor compares a calculated temperature for a determined point in time of a molding cycle with the actual temperature of the molding cycle for that point in time and triggers the flow of temperature control medium for a set period of time to adjust the temperature of the molding cycle. This provides a more exact method of injection molding.

Abstract: In injection molding, a mold forms a wall member, which defines a cavity, by bringing together two mold halves. The cavity wall is formed by a specially machined cavity plate having built-in support columns, fins and ejector pins columns. The plate forms a passageway and in-out flow chambers on the opposite side from the cavity surface which completely surrounds the cavity where coolant or heating circulating carrier flows at high rates. The resulting flow of coolant/heating carrier at high rates can be controlled by special positioning of the flow chambers and creates added turbulence. The built-in support columns, fins and ejector pins also dramatically increase the area of contact of the flow carrier with the cavity plate. The design incorporates built-in support columns and fins which make possible a thinner cavity surface plate by adding strength and structural support to the cavity area.

Abstract: A chase is arranged on a heating plate of a die set. Semiconductor packages are arranged, as products to be heated, in cavities of the chase. A runner is provided in the surface of the chase to feed a molten resin into the cavities. The heating plate has a hole for a rod-like heater and a hole for a temperature monitoring sensor. The rod-like heater is inserted into the heater insertion hole and the sensor is inserted into the sensor insertion hole. The heater has a plurality of mutually independent heat generation areas in its axial direction. The sensor detects temperature at the heat generation areas of the heater. A control section monitors the temperature near the respective heat generation areas of the rod-like heater and sets the temperature at the respective heat generation areas of the rod-like heater to a predetermined level.

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: The state in which a mold is filled with molten resin is held constant at all times by holding constant the temperature of the mold at the start of injection of the resin, thus suppressing a fluctuation in the weight and dimensions of the molded articles. Cooling channel are arranged around a cavity of an injection mold filled with a heated molten resin. Use is made of a response model of a variation in mold temperature in the injection mold. The variation in mold temperature, coolant temperature and temperature of the filling molten resin in a molding cycle are measured, and a parameter (time constant) of the response model is decided using these measured values.

Abstract: A control system for controlling the temperature within process machinery such as the feed assembly in an injection molding machine. The control system provides a six phase process for starting up the machine from cold conditions and controlling the machine temperature to rapidly and accurately attain a command temperature while identifying control parameters for use under steady state conditions for maintaining the command temperature.

Abstract: The invention refers to a method for the reduction of the sag and/or of the different stress profile of a flattened tubular film web produced by a blown film process and made of thermo-plastic synthetic resin, transversely to its longitudinal direction. For the solution of the problem to provide a method according to which the sag and/or the different states of tension transversely to the tubular film web can be easily reduced or eliminated to a maximum degree, the tubular film web is heated along its width and then cooled and/or stretched. Furthermore, the invention refers to an apparatus for carrying out the method.

Abstract: In an intermittent heating apparatus for plasticized fluids in injection or similar moldings, heating medium passages are located outside the electric resistance heating tubes for a liquid or gas to pass therethrough while being in contact with the outer surfaces thereof, also provided is a heating/cooling device having both a high temperature heating medium heated to a high temperature close to the temperature at which said reaction of the raw material is rapidly promoted and a low temperature heating medium of a temperature range where the promotion of said reaction of the raw material can be neglected.

Abstract: Improved optical disks for information storage and holographic imaging, and optical lenses and reflective optical elements are among the difficult-to-mold thermoplastic products which require precision replication of the molding surfaces, in micro detail. By heating (with circulating heat transfer fluids supplied by a hot side reservoir) these mold surfaces to a temperature setpoint sufficiently high to retard solidification and premature viscoelastic skinning of the molten thermoplastic injected into the mold cavity, superior quality molded surfaces can be formed by the plastic, which is then rapidly cooled to solidification (by circulating heat transfer fluids supplied from a cold side reservoir).

Abstract: This invention relates to automating a process for manufacturing articles from plastic, particularly recyclable plastic waste. A lengthened separator head is flanged to a plasticizer to supply melting serially to several molds, by way of mold inlet shut-off mechanism. A preprogrammed control device monitors the filling of a respective mold by way of a pressure sensor in the mold. When the desired filling of the mold has occurred, the inlet shut-off mechanism is closed by the control device and another mold that is ready to be filled is filled with melting by the opening of the corresponding inlet shut-off mechanism at the another mold. In addition, the control device controls the locking and tightening of the mold as well as its opening and emptying.

Abstract: A device for producing synthetic plastic molded sheets including a mold rotatable about at least one axis and receiving a thermoplastic synthetic resin powder which is sequentially heated and cooled by liquid heating and cooling medium admitted into a hollow chamber of the mold, and a housing formed with a housing wall provided with a plurality of bulges for compensating thermal stresses resulting from different materials of the housing wall and a wall of the chamber.

Abstract: A control unit for an injection molding machine comprises a position feedback control system 41, a pressure feedback control system 42, and a velocity minor feedback control system 43 which is used in common to the position and the pressure feedback control systems 41 and 42. A minimum value selector 30-3 selects a smaller one of manipulated variables supplied from the position feedback control system 41 and the pressure feedback control system 42. During pressure control, a position pattern follower 30-4 controls the operation of a position pattern generator 24-2 so as to restart generation of a position pattern at any time.

Abstract: A process for making porous flexible pipes from two feed streams containing a thermoplastic material and a thermoset material, in which the feed streams are delivered to a die head extruder in a substantially compaction-free and segregation-free manner to insure that the feed composition in the extruder is substantially the same as the initial feed composition. The process can be automated so that an operator can manufacture porous flexible pipes of desired porosity and other rheological and mechanical characteristics by simply entering a command which will simultaneously adjust the process parameters such as the temperature and/or pressure inside the extruder, and the post-extrusion tension to meet the special need.

Abstract: Apparatus for molding permits a fluent molding material to be flowed into a mold cavity for shaping into a configuration defined by the mold walls. A master controller controls the transfer of heat with respect to the molding material, to control the temperature of the molding material in a predetermined way. A sensor measures the temperature of the molding material flowed into the cavity and produces feedback signals, which are compared to reference signals indicative of a desired molding material temperature. The apparatus generates a further control signal, which is applied to control the variables of the molding operation, including the temperature of the molding material and the flow rate.

Abstract: A source of radio frequency energy is applied to a low thermal inertia heating element with high thermal conductivity, such as a spool, for rapidly heating the heating element to settable predetermined temperature, which temperature is maintained essentially constant. The heating element is detachably attached about the die of a mold for transferring heat to the die to form, mold, weld or extrude thermoplastic material placed within the mold. Thermal chokes restrict heat transfer from the die to the remainder of the mold. One or more heat sinks draws and dissipates heat from the thermal chokes to maintain cool zones of the mold. Following the heating cycle, upon termination of application of radio frequency energy to the spool, cooling may be accelerated by directing a stream of gas upon the heating element.

Abstract: A pressure transducer for an injection molding machine includes a housing coupled to a nozzle of an injection molding machine. A hollow stress tube, attached to the housing, through which molten material of the injection molding machine flows, bellows in response to pressure from the material. An outer ring having an opening is coupled to the stress tube such that the outer ring expands, causing displacement of the outer ring about the opening, when the stress tube bellows. A displacement sensor is included for determining the displacement of the outer ring about the opening. This displacement is directly proportional to the pressure of the material. In this manner, the pressure transducer determines the pressure of the molten material.

Abstract: A plasticizing apparatus (10) including a barrel (12) having a bore (14) therethrough. An auger (24) and a rotor (30) are positioned in the bore, each extending from opposed ends (16, 18) of the barrel (12) and having ends (26, 34) that are substantially flush. The auger (24) conveys particulate plastic material along the bore (14), the plastic being frictionally melted before passing the auger discharge end (26). The rotor (30) is provided to uniformly heat the melted plastic. Auger (24) and rotor (30) each are associated with independent means for rotating (28, 32) and means for controlling the speed of rotation (50, 52). The speed of rotation of the auger (24) controls the flow rate of plastic through the bore, and the speed of rotation of the rotor (30) controls the temperature of the melted plastic.

Abstract: A temperature control device with high accuracy and stability comprising a heating device and a cooling device which are controlled by separate control circuits for performing proportional control, integral control, derivative control and the like. A ratio of energy supply periods to predetermined control periods is thereby varied, on the basis of a controlled variable calculated from direction, size, change velocity and the like of deviation of actual temperature of a controlled medium from desired set temperature so as to control heating and cooling energy supplies for the heating and cooling devices. The heating energy and cooling energy supplies for the heating and cooling devices can be separately controlled by means of different proportional bands.

Abstract: In a machine for injection molding thermoplastic materials in a molding tool by seriatim injection cycles, wherein an injection pressure stage and a subsequent holding pressure stage are employed, and wherein parameters of a change-over point from the injection pressure to the holding pressure have a trend of varying, a method for regulating the trend of the change-over point in each injection cycle, involving (a) establishing upper and lower pressure, and time boundary target parameters for a working window, (b) establishing upper and lower temperature boundary target parameters for a working band, (c) defining the change-over point within said working window, by specifying a pressure, at a given time, (d)measuring the actual pressure at the time of changing from the injection pressure to the holding pressure, and detecting any pressure and time differences from the boundary target parameters of the working window, (e) measuring the actual temperature, and detecting any temperature differences from the bound

Abstract: An apparatus and a method for producing pasty paraffin from liquid paraffin comprises the use of an agitator for mixing the paraffin during its solidification within a receptacle. The viscosity of the paraffin is controlled by the monitoring of the power of a motor driving the agitator. Also, an apparatus is provided for producing candles in bottles from the pasty paraffin produced hereinabove. The apparatus comprises a filling head which receives the pasty paraffin and a continuous wick. A device is included for positioning a ferrule on the wick with the filling head being adapted for lowering into the bottle for positioning the ferrule at the bottom thereof and being also adapted to inject pasty paraffin in the bottle for setting the ferrule. The filling head is then retracted slowly from the bottle while injecting further paraffin therein for filling to a selected level the bottle.

Abstract: Rapid cooling of molded workpieces such as PET parisons formed in an injection molding machine is provided by a receiver receiving molded workpieces upon ejection from the molding machine, the receiver being transported out of the molding machine to an adjacent position where a cooling head coupled to a source of cooling fluid such as liquid nitrogen directs the fluid toward the surfaces of each workpiece. The cooling head engages and is sealed to the receiver to inhibit the escape of cooling fluid into the atmosphere thereby reducing cost, environmental impact, etc. A cooling program control coupled to the cooling fluid source supplies a discontinuous flow cooling fluid from said source to contact the workpieces only when the cooling head is engaged with and sealed to the receiver. A vacuum unit withdraws cooling fluid from the receiver subsequent to contact between the workpieces and the cooling fluid. The cooling fluid can then recooled and recycled for reuse.

Abstract: Continuous impression forming of three-dimensional products from heated, formable thermoplastic materials between top and bottom mold carriages each having a three-dimensional forming belt mold revolvable around the carriage. Each three-dimensional forming belt mold includes a flexible silicone rubber mold adhered to a multi-ply woven fabric belt. A surface of desired shape on one revolving rubber mold mates with the desired shape of an opposed revolving rubber mold forming a continuously moving mold channel between the mold belts into which is fed hot thermoplastic material at moldable temperature. After discharging molded plastic product from the exit of the moving mold channel, localized surface heat in the rubber molds resulting form contact with hot plastic is removed by air blown directly onto the rubber mold surfaces. Each carriage frame includes a back-up plate coated with low friction coefficient material over which slides a continuously moving belt mold.

Abstract: A screw extruder having a cylinder, an extrusion head, a screw in the cylinder and a motor for driving the screw in rotation has insert members which extend into the cylinder to effect plastification and homogenization of the material being extruded. The web of the screw is provided with annular recesses into which the insert members project. Some of the insert members are stationary, in the form of pins projecting radially into the cylinder, while others are movable so as to vary the extent of their projection into the cylinder. The movable insert members may be pins extending radially into the cylinder and movable radially, rotatable threaded pins extending tangentially into the cylinder, rotatable pins extending tangentially into the cylinder and having non-circular portions in the cylinder, or sector-shaped discs which are movable pivotally.

Abstract: A rotational moulding apparatus includes a device (5) disposed inside the mould for measuring temperature. A processor (6) forming part of a feedback tool (7) enables real time monitoring and control of the moulding process. Identifiable points on the temperature time moulding characteristic are employed to control the operation of the apparatus to optimise the properties of the mouldings obtained.

Abstract: A novel extrusion method and apparatus are disclosed for varying the width of an extruded article which employs the use of thermal pins in the extruder die body and does not involve the use of any mechanical manipulation of the die configuration.

Abstract: A system for monitoring and controlling the output of extruder apparatus for producing a blown synthetic resin film. An infrared imaging system provides for measuring the temperature of the blown film simultaneously at multiple points on the film between the blowing head and the frost line of the film bubble. The multi-dimensional temperature profile measured by an infrared camera is processed in a computer controller in order to provide control inputs to various components of the extruder apparatus. The extruder apparatus is controlled so as to maintain a desired temperature profile substantially at that which is known to provide a high quality end product.

Abstract: An apparatus for injecting molding material into a self-clamping mole. The apparatus includes a support frame with spaced plates and support bars interconnecting the plates, and a C-shaped opening formed in the plates. An injector is included for injecting molding material into the self-clamping mold under pressure, and an extruder for providing molding material to the injector. Temperature controllers are also provided for controlling the temperature of the molding material within the injector and extruder. A lift mechanism supported on the frame provides clamped engagement between the self-clamping mold and the frame. During the injection operation wherein the injector is engaged with the mold, the lift mechanism clamps the mold to resist internal mold forces resulting from the injection of molding material.

Abstract: An arrangement for charging a plurality of molds for processing plastic materials with at least two sources of fluid and for temperature regulating the molds. Each mold of the arrangement is provided with a feed inlet conduit to which a three-way valve is connected. The feed inlet conduit is also connected to the two sources of fluid and each mold further includes an outlet conduit with a thermostat valve. A distribution element is connected to the feed inlet conduit and to the two sources of fluid. The three-way valve is connected to least two sources of fluid. This three-way valve has an outlet which is connected to the distribution element. A heating element is connected in each inlet conduit of each mold. A temperature regulator is mounted in each outlet of each mold for each heating element. This temperature regulator is coacts with the thermostat valve which is mounted downstream of each temperature regulator in each outlet conduit of each mold.

Abstract: A method and apparatus for forming a molded plastic part such as a body side molding for a motor vehicle in which a ribbon of plastic material is extruded through a shaping die of an extruder and is thereafter moved through a runner and into an elongated closed end mold cavity having a size and shape conforming to the body side molding. The cross-sectional area of the extruded ribbon, the runner and the mold cavity are substantially equal and the entire path of the plastic material moving through the extruder, runner and mold cavity is maintained at a temperature above the melting point of the plastic material so that the plastic material moves smoothly and quiescently along the path under relatively low pressure and with minimal disturbance. The invention process substantially eliminates swirling and streaking of metal particles which are commonly dispersed in the plastic material to give the body side molding a metallicized, glossy appearance.

Abstract: A method for molding is disclosed in which a fluent molding material is flowed into a cavity of a mold, which is then shaped into a configuration defined by the mold. Control signals which are applied by operating a master controller to control the transfer of heat with respect to the molding material, in order to predeterminately control the temperature of the molding material as it flows into and is retained within the mold. The temperature of the molding material flowed into the cavity is sensed, and feedback signals are generated relating to the sensed temperature. The feedback signals are compared to reference signals indicative of a desired molding material temperature and a further control signal is generated which is applied to control the variables of the molding operation, including the temperature of the molding material.

Abstract: A master frame supports interchangeable mold inserts, each of which is provided with its own electrical heater and associated wiring. A recess is provided in the master frame to allow for lateral movement of the wiring, heater and mold inserts as a unit during installation and replacement. A closure member in the form of a thermocouple retainer is provided to support a temperature-controlling thermocouple inwardly of a hole within each mold insert as well as to close the recess during a molding operation.

Abstract: A process and apparatus for controlling the manufacture of mineral fibers, in particular glass fibers, by use of a fiber-drawing process using internal centrifuging in a centrifuger. The peripheral strip is pierced by a large number of outlet orifices and the radiation emitted superficially by the peripheral strip is measured in order to determine the temperature of points of the peripheral strip and the vertical coordinate of each of the points measured.

Abstract: An improved apparatus providing for uniformity of web thickness. In one aspect, the apparatus includes a plurality of gap-controlling, thermal energy sources, and in heat-exchange communication with the thermal energy sources, an assembly for compensating for temperature variation proximate to the thermal energy sources and across the apparatus width. The thermal compensating assembly includes a heat exchange jacket, and in combination therewith, a heat-exchanging, working fluid that undergoes a phase change in performing its heat exchange function.In another aspect of the invention, the apparatus includes an element disposed along an exit slot-forming lip, that reduces localized thermal gradients along the lip. This element functions as a heat sink and a heat source proximate to the lip gap, and likewise includes a heat-exchanging, working fluid that undergoes a phase change.

Abstract: In a mixer comprising a body defining a mixing chamber in which two rotors are rotatably mounted, a processability sensing system is disposed in a port in the body. The system is operative to monitor the flow and deformation characteristics of the material being mixed. It is connected to a feedback control loop which leads to a computerised control operative to control mixing characteristics. This enables mixing to be closely controlled to provide a better product.

Abstract: A rotary plastic blow molding machine (20) including a base (22), a wheel (24) mounted for rotation on the base about a rotational axis A and a programmable logic controller (PLC) (100) mounted on the wheel for rotation therewith to control operation of a plurality of mold stations (40) on the wheel. The blow molding machine (20) as disclosed also has at least one sensor (62) mounted on the wheel (24) for rotation therewith to sense an operating parameter of each mold station and to generate an associated operation signal. The PLC (100) is coupled to the at least one sensor (62), processes the sensed operation signal and controls the machine (20) operation in response to the signal.

Abstract: Continuous process and apparatus form products from thermoplastic materials between top and bottom mold carriages. A flexible silicone rubber mold on a fiber belt continuously moves around each carriage frame. A surface of desired shape on one rubber mold mates with the desired shape of an opposed rubber mold forming a continuously moving mold channel into which is fed hot thermoplastic material at moldable temperature. After discharging the molded plastic product from the moving mold channel, localized surface heat in the molds resulting from contact with hot plastic is removed from the belt molds by air blown onto mold surfaces. Each carriage frame includes a back-up plate coated with low friction coefficient material over which slides a continuously moving belt mold. These slippery plates have numerous air-bearing holes feeding high pressure air between them and the respective moving fiber belt for reducing friction and wear.

Abstract: A method and an apparatus for treating contaminated plastics waste, comprising densifying contaminated plastics waste by causing the waste to pass through a heating zone to produce molten contaminated plastics, and causing the molten contaminated plastics to flow continuously out of the heating zone under the influence of gravity.

Abstract: A method and apparatus for thermically processing a material, such as a plastic material made of PET, in contact with a very thin heating layer that is provided on a body, such as a blow-mold. The intensity of current supplied to the heating layer is controlled as a function of the medium temperature in the heating layer to allow the heating layer to very rapidly heat up the plastic material contacting the heating layer. After switching off the heating current the plastic material is rapidly cooled down to the temperature of the body carrying the heating layer. This process may be applied to the heat setting process of blow-molded hollow articles made of PET.

Abstract: The present invention provides a multi-ply molding hot-runner mold including a plurality of nozzle bodies for injecting a plurality of different resin materials to form a multi-ply product. The hot-runner mold comprises a plurality of hot-runner blocks each having a runner for conducting each resin material into the corresponding nozzle body. The hot-runner blocks are stacked one above another with a thermal insulation layer therebetween. Each of the hot-runner blocks includes temperature control means for maintaining the hot-runner blocks at its own molding temperature. Connecting blocks for conducting the resin material from the lower block to the upper block are provided between each adjacent hot-runner block. Between each adjacent hot-runner block there are provided holding members and thermal insulation layers.

Abstract: An apparatus for the production of molded shells and bodies of plastic material by a rotational molding procedure within an electroplate mold includes a double-walled hollow body which is heated up and cooled down by a heating and cooling medium. A box which contains plastic material can be fitted on to the mold. The mold and the box are jointly pivotable so that the plastic material can pass into the mold and fuse at the wall of the mold. At its rear wall, which is remote from the internal contour which produces the molding action, the double-walled hollow body has a multiplicity of intake and discharge openings for the heating and cooling medium so that heating and cooling can be effected specifically and quickly. The total discharge cross-section is greater than the total feed cross-section whereby the hollow body remains substantially pressure-less.

Abstract: A conveyor belt has edges with longitudinally extending profiles formed as grooves or elevations for sealing and guiding. An apparatus for producing belts with profiled edges uses a cutting device and profiled molds to form profiles in the belt and its edge while the belt is guided and supported by rolls. The apparatus further includes a cutter which forms a groove in the conveyor belt and which allows lateral guiding of the bolt in relation to the mold.

Abstract: An apparatus for use in gas assisted injection molding of plastic material so as to form an injection molded product includes a pair of mold members defining when closed a sealed cavity. A first opening is provided in one of the mold members for allowing the injection of a plastic material into the cavity. A device is provided to supply a pressurized gas and a second opening is provided in one of the mold members for allowing the injection of the pressurized gas into the cavity. A probe is located in the second opening and is adapted to be reciprocated therein from a retracted position to an extended position. The probe has a first end adapted to selectively extend into the cavity, a second end, and a longitudinally extending bore which terminates in a port located adjacent the first end. The bore is used to guide the gas into the cavity. A device is provided for reciprocating the probe in relation to the cavity.

Abstract: In a method of checking the gelling process after pouring a reactive resin system into a production mould, the gelling behavior of a resin system is detected by means of calibration measurements and stored. Temperature patterns of the resin system are detected and, for each temperature pattern, the temperature at which the gelling point lies is determined. A scalar value and the gelling moment temperature are associated with each temperature pattern. On carrying out a checking measurement inside a production mould, the temperature patterns at various sites inside the production mould are detected using a large number of thermocouples. Scalar values are obtained from the temperature patterns and are compared with the scalar values established during the calibration measurement in order to establish gelling moment temperatures. The particular advantage of the method described is that the checking measurement of a production mould requires the use only of thermocouples and not of gelling point probes.

Abstract: In a heating/cooling unit for selectively heating or cooling a set of dies, oil received in a reservoir is supplied to a flow direction changeover valve by a first oil pump. In a stably mode, oil is returned to the reservoir through the changeover valve and a heat exchanger. In a heating mode, the oil is supplied to a second oil pump from the changeover valve through a check valve. The second oil pump supplies the oil to an oil heater, and the heated oil is introduced into a fluid path formed in the dies to heat the dies. The oil discharged from the fluid path of the dies is returned to the second oil pump. Thus, the heated oil is circulated in a closed loop in the heating mode. In a cooling mode, new oil is supplied to the fluid path of the dies from the changeover valve and the oil discharged from the fluid path is guided to the heat exchanger through a switching valve and the cooling oil is returned to the reservoir.