Abstract: An injection molding apparatus utilizing an injection molding machine having a pair of separable mold elements forming a mold cavity therebetween and arranged for separation for the removal of the molded product, means for opening and closing the mold elements, and injection means for injecting the moldable material into the mold cavity at a first pressure and for exerting a second pressure on the moldable material as it cures in the cavity. The apparatus provides data acquisition and application in the operation of the injection machine. The apparatus includes means for measuring the separation of the mold elements during the injection of the moldable material, and means for causing the injection pressure from the first pressure to the second pressure upon detecting a predetermined separation known to produce an acceptable product. Means is provided for maintaining the second pressure until the thermoplastic material has cured. The mold is then opened and the cured product is ejected.

Abstract: An injection molding machine using a linear motion type electric motor (10, 20), as a drive source, is provided, which is simple and compact in construction. The linear motion type electric motor includes a non-magnetic shaft (21) on which yokes (22) and permanent magnets (23) are alternately fitted, and an annular stator (10) having an outer tube (11) within which cores (12) and printed type coils (13-18) are alternately disposed, the shaft extending through the stator. Upon supply of three-phase alternating currect to the coils, a screw of the injection molding machine coupled to the shaft is moved in unison with the shaft to thereby perform injection operation.

Abstract: An injection molding method utilizing an injection molding machine having a pair of separable mold elements forming a mold cavity therebetween and arranged for separation for the removal of the molded product, means for opening and closing the mold elements, and injection means for injecting a moldable material into the mold cavity at a first pressure and for exerting a second pressure on the moldable material as it cures in the cavity. The method relates to data acquisition and application in the operation of the injection machine and includes the steps of closing the mold elements, injecting a moldable material into the mold cavity at the first pressure, measuring the separation of the mold elements during the injection of the moldable material, changing the injection pressure from the first pressure to the second pressure upon detecting a predetermined separation known to produce an acceptable product.

Abstract: A trapped rubber molding method including a die positioned within a fixed-volume, rigid mold, the die being surrounded by an integral solid silicone rubber material which has been cured within the mold at an elevated temperature. The die and mold closure are thermally isolated from the remainder of the mold. The die and the silicone rubber material adjacent thereto are selectively heated and cooled. The opposite end of the mold is selectively heated and cooled. This configuration results in the ability to independently control temperature and pressure on the molded part during the molding process.

Abstract: A method for the supervision of injection molding including monitoring an internal die pressure of molten resin flowing through a resin passageway in a mold to form a monitored waveform; displaying the monitored wavefrom together with a predetermined reference waveform on a display unit such as a CRT, and comparing the monitored waveform with an allowable value of the reference waveform to determine any abnormality caused in a molding process. The injection molding can be supervised with accuracy on the basis of the reference waveform representing the optimum internal die pressure, thereby increasing the quality of molded articles.

Abstract: An injection molding process in which an injection of a molten resin into a cavity is performed under such a condition that an internal resin pressure upon filling of the cavity with the molten resin is lower than a maximum internal resin pressure required upon pressure holding after the filling.

Abstract: A press particularly for forming a blocklike tablet or compact from powder. A die is split into opposed halves for defining a die opening vertically therethrough. The die is supported within a carrier having an openable front door. The carrier is mounted on a carriage which is horizontally rollable on a base frame between compacting and loading positions. The carrier preferably has limited resilient floating movement relative to the carriage in the vertical direction. A first pressure cylinder has its housing carried by the carrier so that its piston rod extends horizontally for direct compression against a rear side of the die. A second pressure cylinder has its housing mounted on the frame and its piston rod extending vertically downwardly for compression against a punch which projects downwardly into the die opening to compress the powders therein against a lower punch. The die is vertically aligned with the piston rod of this second cylinder only when the carriage is in the compacting position.

Abstract: In an injection molding machine having at least four motors (18 to 21) and a control section (22) for controlling the four motors to carry out a predetermined injection molding process divided into a plurality of steps, the four motors are grouped into first and second groups so that the motors of each group have driving durations which are not overlapped with one another and which may be overlapped with those of the motors of another group. The control section has first and second control unit (24 and 25) coupled to the first-group motors and the second-group motors for individually and selectively controlling the first-group motors and the second-group motors.

Abstract: In a method and a device for making shaped objects from plastic refuse plasticized in a roller extruder under pressure and ejected from the nozzle of the extruder a plurality of molds are provided transported to the extruder, filled thereby and transported therefrom. Each mold has at the end face a plate having a filling opening. During the filling process this plate sealingly overlaps the surface surrounding the nozzle so that the mold can be filled with plasticized plastic under the pressure generated in the roller extruder.

Abstract: An extrusion molding equipment for a multi-layer parison which includes an operation position detecting device for detecting an operation position of an accumulator extruding an layer of resin material invisible from outside the parison. A pressure detecting device is provided for detecting pressure of the inner resin material in an inner resin conduit. An extrusion amount control device for the inner resin material is also provided for controlling an extrusion amount of the inner resin by the use of a signal indicating the operation position from the operation position detecting device, and a signal indicating the pressure from the pressure detecting device.

Abstract: A compression molding method includes detecting actual internal die pressure of molding material filled into a mold cavity, and regulating the compressive force exerted on the molding material in the mold cavity so as to conform the detected internal die pressure with a predetermined reference internal die pressure. The compressive force exerted on the molding material is controlled by a mold clamping mechanism or an extruder in accordance with the prescribed reference internal die pressure given in the form of a waveform, thereby to keep the actual internal die pressure of the molding material in the optimum condition. Consequently, molded products of high quality can be produced continuously.

Abstract: Attached to the eccentric studs (25) for supporting and positioning press rollers (20) relative to an inner surface of the die (21) of a pellet mill are levers (30). Linked to the levers (30) is an adjusting means (31) that is provided with a position controller (47) whose position measuring means is constructed as part of the adjusting means (31) for the position of the press rollers (20). In this fashion, the gaps between press rollers (20) and die (21) can be regulated very exactly from the outside.

Abstract: A process and apparatus for producing a reclosable container stock with adhered occludable closure strip portions, said apparatus comprising a rotatable lay-on roll having circumferential grooves therein, means to advance the closure strip portions to the lay-on roll, a rotatable casting cylinder positioned opposite the lay-on roll, means for extruding a molten plastic film onto the casting cylinder so that the film adheres to the closure strip portions, and means for cooling the resulting reclosable container stock with adhered closure strip portions.

Abstract: In a method of operating an injection compression molding machine having a stationary metal mold, a movable metal mold, an oil pressure actuator for advancing the movable metal mold toward the stationary metal mold to form a mold cavity therebetween with a predetermined compression clearance .delta. left between the movable and stationary metal molds, a heating cylinder adapted to engage with the stationary metal mold, a hopper for supplying a thermoplastic resin into the heating cylinder, a screw contained in the heating cylinder for injecting molten metal into the mold cavity, an oil pressure motor for rotating the screw and a piston cylinder unit for reciprocating the screw through the heating cylinder, the molten resin is filled in the mold cavity by advancing the screw and the advancement of the movable metal mold is started when the screw reaches a predetermined set position during an injection stroke so as to reduce the compression clearance .delta.

Abstract: A differential screw adjusting mechanism comprised of an externally and internally threaded adjusting nut which has a plurality of slots formed along its length. The internal threads of the adjusting nut cooperatively and threadedly engage screw threads at the end of each of the expansion rods. The rods are in turn fixed to the lip of the die via set screws or jam nuts. A spool having an internally threaded diameter and a slot along its length is engaged to the external threads of the adjusting nut. The head of the spool has a flattened portion to limit rotation of the spool when clamped in place. Thus, the slotted adjusting nut is overfit with the slotted spool. The entire assembly of spool, nut, and rod is clamped in place via a clamping arrangement affixed to the die. The tightening of the clamp serves to close the spool via the slot over the nut, and in turn, the nut, via its slots, over the rod.

Abstract: A method and apparatus for controlling back pressure in an injection molding machine. Forward and backward movements of an injection plunger are converted into rotational motion and the turning force and back pressure of the injection plunger during the step of charging material are controlled. An electric motor serves for carrying out back pressure control and a torque limiting control function is performed to limit the output torque of the motor according to the magnitude of a set value of back pressure.

Abstract: In an injection molding apparatus using a motor as a driving source, the injection speed and the injection pressure are controlled via a speed sensor, a pressure sensor and a closed loop control system, to provide higher accuracy and better operability during switching of the apparatus from an injection speed control phase to an injection pressure control phase and thereafter to a back pressure control phase.

Abstract: A flow molding process and associated molding apparatus for making plastic parts employing a radio-frequency heating field. In a two-piece mold, a diaphragm is supported thereacross and over a foam plastic compound that is disposed in the bottom half of the mold. A fluid is adapted to be introduced into the mold against the diaphragm. The introduction of this fluid is controlled to initially inject the fluid into the mold to cause deflection of the diaphragm to thus expel substantially all air from the mold and to thereafter extract the fluid from the mold during the heating cycle as the material expands, the extraction causing a vacuum that assists in the plastic foam compound expansion.

Abstract: A method and an apparatus for automatic zero adjustment of an injection-molding machine, in which an axis driven by a servomotor can be automatically returned to its origin with accuracy and speed. When a one-revolution signal is produced after the axis reaches a deceleration position, a preset coordinate position of a reference point is written in a current-value register. Subsequently, when the axis driven toward an absolute position reaches the absolute position, the preset coordinate position of the reference point is corrected with use of a correction value calculated on the basis of a known coordinate position of the absolute position and the register value. When the axis driven toward the reference point reaches the corrected position, the preset reference point coordinate position is written in the current-value register.

Abstract: A hydraulic actuator assembly for use in a mold clamping unit of an injection molding machine. The actuator assembly serves as a rapid-travel drive for mold opening and closing movements and as a source of elevated mold clamping pressure. Among the hydraulic elements contributing to the operation of the mold clamping unit are a power piston for effecting elevated mold clamping pressures and a drive piston for effecting rapid die closing movements. With the hydraulic actuator system of the present invention, it is possible to control the operation of the mold clamping unit based on two-sided hydraulic influencing of the power piston and the drive piston.

Abstract: There is provided a die-touch position detecting apparatus capable of automatically and accurately detecting a die-touch position of a direct mold clamping mechanism driven by means of a servomotor. A numerical control unit (10) performs pulse distribution to a servo-circuit (30) in response to a die-touch position detecting operation command inputted through a manual data input device (17), thereby moving a movable platen toward a stationary platen. When the amount of errors accumulated in an error register (31) of the servo-circuit exceeds a predetermined value, the numerical control device stops the pulse distribution to the servo-circuit, and then calculates the die-touch position in response to the amount of pulse distribution to the servo-circuit and the amount of errors.

Abstract: A numerical control method and an apparatus therefor, in which a mold opening operation or an eject operation is performed during a metering operation so that the injection-molding cycle time is shortened. When a cooling period terminates or mold opening is completed during the metering operation, a programmable machine controller for sequentially controlling an injection-molding machine delivers information specifying a clamp axis or an eject axis, the displacement, moving speed, and moving direction of the axis, and a step feed command to a numerical control unit for controlling servomotors for axes of the injection-molding machine, through a common RAM. Pulse distribution for the clamp axis or the eject axis, based on this information, and pulse distribution for a screw rotating axis are alternately executed by a numerical control unit, which responds to the step feed command.

Abstract: In a method of controlling an injection molding machine wherein a pressure holding step is controlled in multiple steps, the transfer points of respective holding pressures are transferred in accordance with the temperature of injected resin or a metal mold detected by a temperature sensor provided for the metal mold.

Abstract: A switching control method which can smoothly effect transfer from a pressure holding step to a metering and kneading step in an injection-molding machine employing a servomotor as an injection shaft driving source for axially driving a screw. At completion of the pressure holding step, follow-up of an error register of a servo circuit driving the injection shaft servomotor is effected so as to bring an error amount accumulated within the error register to zero (steps S6 to S8). A value of torque limit acting on the servomotor is then switched from a set value for pressure holding to a set value for metering and kneading (step S11). Further, the follow-up of the error register is again executed over a predetermined period of time from the time of execution of the switching of the torque limit (step S13). Subsequently, transfer is effected to the metering and kneading step (step S14).

Abstract: The preformed assembly of a transparent sheet material and a gasket adhered to the periphery thereof, and the method for producing the assembly. Preferably, the sheet material is glass and the gasket is formed of a thermosetting polyurethane material. The material, curable to produce the gasket, is injected into a mold cavity and thence by controlling the attendant parameters, the autogeneous pressure incident to polymerization causes the material to be urged into intimate contact with mold cavity and the sheet material. After the material has been cured sufficiently, the resultant assembly is removed from the mold cavity.

Abstract: An injection molding method operable in conjunction with an injection molding machine having an injection screw which rotates and moves backward while a preset dosage of molding material is injected into the molding machine. As the injection screw moves backward its arrival at a predetermined point relative to a discharge nozzle is detected by a sensor which initiates stoppage of feeding of material into the machine. Further backward movement of the injection screw resulting from internal pressure in the injection cylinder is arrested by an adjustably locatable stopper, disposed behind the injection screw. The stopper is designed to be located at a position that produces molded products of consistent quality. Further, in accordance with a preferred embodiment of the invention, the stop position of the injection screw is also used as a starting point for the injection screw in a subsequent injection step during which the dosage of material is injected into a molding cavity.

Abstract: When the mold of plastic injection molding machine is locked, the closing force (K) is measured at the knuckle joint system during a predetermined number of operating cycles (Z). A mean value is computed from these actual value measurements (Si) and if it is within a predetermined tolerance zone (T) around a set-point value (So), no control intervention takes place. But if this mean value is outside of the tolerance zone (T) but in a control zone (R) limited by alarm limits (A), a control intervention takes place by stepwise changing the installed height of the mold until the actual value measured after each operating cycle is again within the tolerance zone (T). The measurement is repeated over another operating period (B); if those measurements stay within the control zone (R), a new mean value is computed only at the end of this operating period and a corresponding decision is made whether or not a control intervention should take place.

Abstract: A press has upper and lower platens which can be moved towards and away from one another. Four hydraulic leveling cylinders are mounted in a vertical orientation on the lower platen for purposes of platen parallelism control. In preferred form, each cylinder has a piston rod which engages an associated post on the upper platen as the platens approach one another. The piston rod and associated piston are formed with a longitudinal bore open at the upper piston rod end, and a rigid shaft is mounted in the bore with a lower end extending through the bottom of the cylinder housing. A coil spring in the interior of the piston rod urges the rigid shaft upwardly until a collar formed on the shaft engages a stop surface, the upper shaft end then being flush with the upper piston rod end. The associated post is fixed to the upper press platen in-line with the piston rod and has an internal passage in which is located a stud-like shaft that engages the rigid shaft mounted in the piston rod.

Abstract: An apparatus for molding and curing a resin matrix composite material under pressure and heat by a use of a bag provided in an autoclave for covering the material and applying the pressure to the material.

Abstract: In an injection molding process, male and female dies are first clamped together by a prescribed clamping force to provide surfaces defining a cavity of a prescribed extruded area therebetween. Then, a molten resin is injected at a prescribed injection pressure into the cavity until the cavity is filled with the molten resin. Subsequently, the molten resin filled in the cavity is held at a prescribed holding pressure, so that the resin within the cavity solidifies to produce a molded article. The injection pressure in the injecting step is controlled so as to decrease immediately before the cavity is filled with the molten resin to thereby prevent a pressure boost from occurring upon the termination of the injecting step. The holding pressure in the holding step is controlled in such a manner that a maximum of the pressure of the resin within the cavity in the holding step is higher than a maximum of the pressure of the resin within the cavity in the injecting step.

Abstract: A method for checking or controlling cross linking in products made of elastomeric material has a mold of a fixed volume provided with at least one pressure sensor detecting pressure variations in the mold during cross linking in order to obatin data referring to the progress of the cross linking in the case of laboratory applications, while in manufacturing, it can provide an automatic control of the duration of the various states of the manufacturing cycle by means of microprocessor controlled equipment to which such sensors are connected. The peak pressure reached in the mold is measured and a decrease in its gradient as time passes is detected. Subsequently an increase in the gradient is detected and the time required to obtain a variation of a pre-established order is determined. This data is used to obtain information on how cross linking is progressing and for automatically controlling the manufacturing equipment.

Abstract: In a nozzle pressing and contacting process, a mold clamping process, and an injection process in an injection molding operation, a movable side, such as constituting a nozzle portion or screw of an injection apparatus, or a movable mold of a molding apparatus, is moved towards and contacted with a stationary side, such as constituting a mold or molding machine, or a stationary mold under a speed controlled condition. When the movable side approaches the stationary side, the pressure acting on the stationary side is measured and when the measured pressure reaches a predetermined set pressure, the speed control is switched to a pressure control to accurately and smoothly bring the movable side into contact with the stationary side.

Abstract: Control and monitoring instrumentation for a high speed double rotary tablet press mechanism is disclosed. Each tablet press side has strain gauges producing signals indicative of table compression. The strain gauges generate control signals received by a peak detector, which holds the maximum strain signal. The peak signals are converted to digital form and provided to a microprocessor that first controls operation of the reject gate and regulates tablet consistency by controlling powder fill into the dies, and second, passes information to RAM. The RAM is shared by a master CPU, clocked 180.degree. out of phase with the microprocessor. The master CPU produces either a CRT or printed output of both raw and statistically abstracted tablet press data.

Abstract: A suckback method and apparatus is capable of positively effecting a suckback operation in an injection molding machine using a servomotor as an injection axis drive source for axially driving a screw. When the screw reaches a metering completion position, screw rotation is stopped and a follow-up operation for an error register is carried out so that an error amount accumulated in the error register becomes equal to zero (steps S1, S4, S5). Then, a torque limit for the servomotor and for application of back pressure is released (step S8), and the screw is driven backwardly by the servomotor by a predetermined suckback amount (step 11).

Abstract: An improvement for casting machines is provided which assures a constant thickness and density of extruded material by varying the speed of nip forming rolls.

Abstract: An analytical technique for controlling the curing process of fiber-reinforced composite materials that are formed using thermosetting resins. The technique is the percent gel method and involves development of a time-to-gel equation as a function of temperature. From this equation a rate-of-gel equation is then determined, and a percent gel is calculated which is the product of rate-of-gel times time. Percent gel accounting is used to control the proper pressure application point in an autoclave cure process to achieve desired properties in a production composite part.

Abstract: A method of making a fiber reinforced part by compression molding under heat and pressure a glass fiber reinforced thermosetting resin composition at an initial high pressure for a short period of time and then substantially reducing the pressure for a longer period of time to form an almost cured FRP part at which time there is applied to the exterior or outer surface of the FRP part an in-mold coating composition and heat and pressure are continued to cure the in-mold coating composition and to complete the cure of the FRP part. During the molding process the temperature gradient across, or the temperature non-uniformities of, the molding or working surfaces of the mold halves is less than about 5.degree. C.

Abstract: A method of forming a hollow reinforced fiber structure includes the steps of providing fiber reinforced material around a flexible expandable member and placing the resulting package inside of a mold which includes inner surfaces conforming to the shape of the structure being formed. A second expandable means is included in the mold on both sides of the package. After the mold is closed, pressure is applied to force the second expandable means against the fiber reinforced material. Resin is injected into the fiber reinforced material. The pressure is then decreased in the second expandable means as inflatable member is expanded to force the fiber material to conform to the inner surfaces of the mold. The fiber material is then cured to form the structure.

Abstract: An error detector for various set values is provided which is incorporated in an injection-molding machine of a type controlled by a numerical control unit (1).In order to prevent wrong operations of the injection-molding machine due to setting errors of set values, in the error detector, discrimination means (3) determines whether set values of various items of forming conditions, inputted through input means (14), fulfill requirements related to the items. If the inputted set values fulfill the requirements, they are stored in memory means (6). If not, an alarm is delivered.

Abstract: A method for injection molding a material involving bringing the interior of a tightly sealed injection mold under a high vacuum, then injecting the material into the interior of the injection mold at an ultrahigh speed in the vicinity of a speed at which adiabatic change is exerted on the material in accordance with a predetermined pattern of internal pressure so as to fill the interior of the injection mold with the material, and molding the material under low pressure. An injection molding apparatus used for carrying out the aforementioned method is capable of bringing the interior of the injection mold to a high vacuum.

Abstract: An improvement for casting machines is provided which displays a correct nip measurement based on the relative position of cooperating rolls and the thermal expansion of the rolls.

Abstract: A mold for forming the vial and cap and for seating the cap on the vial prior to ejecting the vial from the mold is provided and includes a frame for the mold, a first mold half arranged on the frame, and a second mold half movable arranged relative to the first mold half so as to form a mold cavity therebetween. The mold produces a vial and cap including smooth radii provided at several locations to facilitate the seating of the cap on the vial.

Abstract: A method of mold opening/closing speed control wherein an opening/closing speed switching position for molds in a mold clamping unit in an injection molding apparatus can be taught by a control device. The control device is set in a teaching mode (101), a servo motor (M) is driven at a low speed to move (102) the molds, speed switching position P1, P2 and P3 are stored (103, 104, 205, 106, 109) by a teaching device and opening/closing speed control of the molds is performed (110, 123) by the servo motor in accordance with the stored positions.

Abstract: An apparatus for checking or controlling cross-linking in products made of elastomeric material which is the object of the present invention, comprises a mold of a fixed volume provided with at least one pressure sensor able to detect pressure variations in the mould during cross-linking in order to obtain data referring to the progress of the cross-linking in the case of laboratory applications, while, should the apparatus be used in manufacturing, it can provide an automatic control of the duration of the various stages of the manufacturing cycle by means of microprocessor controlled equipment to which such sensors are connected.

Abstract: In a heat displacing type die adapted to extrude a sheet of molten resin, a heat displacing unit provided with a heater is secured to an upper die block. A lip gap is defined between a flexible lid and a stationary lip respectively provided for the upper and lower die blocks. The lower end of a bolt extending through the heat displacing unit is normally in contact with or secured to the flexible lip while the upper end is secured to the upper portion of the heat displacing unit. In a modified embodiment the bolt is air cooled.

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: A rotational plastic compression molding apparatus including a plurality of circumferentially spaced female molds and a plurality of circumferentially spaced male molds cooperating respectively with the plurality of the female molds. The female molds and the male molds are rotated in synchronism and thus moved round successively through a material loading zone, a compression molding zone and an article discharge zone. In the material loading zone and the article discharge zone, each said female mold and each corresponding mold are maintained in a spaced-apart inoperative relation, and in the compression molding zone, they are maintained in an approaching operative relation to define a mold space therebetween. In the material loading zone, a heat-melted plastic material is loaded in the female molds, and in the article discharge zone, the compression-molded plastic article is discharged from between each said female mold and each corresponding male mold.

Abstract: A coating method and apparatus using an extrusion head to apply a liquid film to a running web. The thickness of the film is measured at two transverse points and a roller conveying the web is tilted to correct any difference. The amount of tilt per roller with a roller bearing span of 750 mm is 0.5 to 20 mm, preferably 0.5 to 15 mm.

Abstract: A monitor device for a screw position and an internal die pressure is used by an injection molding machine for driving a screw (29) by a servo motor (27). During injection, a sequentially updated address from an address generator (20) is supplied to first and second memories (16, 18) through an address switching circuit (21) to designate addresses of the memories (16, 18) so that the output from a pulse counter (15), which represents the screw position, and the output from an analog/digital converter (17), which represents the internal pressure of a die (30), are sequentially stored in the first and second memories (16, 18). During monitoring, the values stored in the first and second memories (16, 18) are read out through the address switching circuit (21) which has performed switching, and the relationship between the screw position and the internal die pressure is displayed on a display unit (25).

Abstract: Attached to the eccentric studs (25) for supporting and positioning press rollers (b 20) relative to an inner surface of the die (21) of a pellet mill are levers (30). Linked to the levers (30) is a cylinder/piston unit (31) that is provided with a position controller (47) whose position measuring means is constructed as part of the adjusting means (31) for the position of the press rollers (20). In this fashion, the gaps between press rollers (20) and die (21) can be regulated very exactly from the outside.