Abstract: A method for rapid manufacturing of three dimensional discontinuous fiber preforms is provided. The method includes the deposition of a polymeric material containing fibers on a surface to form a tailored charge for compression molding. The reinforced polymeric material may be a thermoplastic or a reactive polymer with viscosity low enough to allow flow through an orifice during deposition, yet high enough zero shear viscosity to retain the approximate shape of the deposited charge. The material can be deposited in a predetermined pattern to induce the desired mechanical properties through alignment of the fibers. This deposition can be performed in a single layer or in multiple layers. The alignment is achieved passively by shear alignment of the fibers or actively through fiber orientation control or mixing. The fibers can be of the desired material, length, and morphology, including short and long filaments.

Abstract: Embodiments of the present technology may include a method of making a thermoplastic composite concentrates. The method may include melting a low-viscosity reactive resin to form a molten reactive resin. The method may also include fully impregnating a plurality of continuous fibers with the molten reactive resin in an impregnation device. The method may further include polymerizing the molten reactive resin to form a thermoplastic composite strand. In addition, the method may include chopping the thermoplastic composite strand into a plurality of pellets to form a plurality of thermoplastic composite concentrates.

Abstract: Embodiments of the present technology may include a method of making a thermoplastic composite strand. The method may include melting a reactive thermoplastic resin to form a molten reactive resin. The method may also include fully impregnating a plurality of continuous fibers with the molten reactive resin in an impregnation device. The method may further include polymerizing the molten reactive resin to form a thermoplastic resin matrix. In addition, the method may include cooling the thermoplastic resin matrix to form a thermoplastic composite strand.

Abstract: A system for making PET objects including a means for reacting a first PET precursor and a second PET precursor to produce a PET melt; a means for flowing the PET melt to a valve having at least two outlets; a means for flowing the PET melt from at least one of the at least two outlets to at least one die forming line and one pelletizing (cutter) line. A means for controlling individually the mass flow of the PET melt in each of the at least two system lines independently of the other and a means for forming the PET objects from the PET melt. The control scheme is a combination of a feed forward system as well as a feedback loop. The entire control scheme is part of the overall system PLC. The fine tuning of the pressure at the outlet of the die forming loop is controllers to less than +/?1 bar to obtain maximum control of formed part.

Abstract: A three-dimensional printing system to print three-dimensional objects and a method of printed are disclosed. The system includes one or more printing heads, two or more cartridges, two or more sensors configured to determine the status of building material in the cartridges and a controller configured to receive data from the sensors and to control switching of building material supply from one cartridge to another. The printing method includes measuring data from two or more sensors to determine the status of the three-dimensional building material in the cartridges, controlling supply of the building material based on data received from the sensors and controlling switching of building material supply from one cartridge to another.

Abstract: A NdFeB sintered magnet production system including: a first weight unit for measuring the mold weight when the alloy powder is not yet filled; a guide attachment unit to extend the mold cavity with a guide to form a supply cavity with a predetermined volume; a powder supply unit for supplying the alloy powder into the supply cavity so that the alloy powder volume is equal to the supply cavity capacity; a filling unit for pressing the alloy powder contained in the supply cavity into the mold cavity to densify the alloy powder to the filling density; a second weight unit for measuring the mold weight after being filled with the alloy powder; and a controlling unit for computing the alloy powder weight filled into the mold cavity based on the difference between the measurement value from each of the first weight unit and the second weight unit.

Abstract: A dry-cast concrete block molding machine including an apparatus which successively positions block mold trays into the mold box of the molding machine with the apparatus pushing a molded block from the mold box as an empty mold tray is moved into the mold box. The machine also includes a magazine-like structure which has empty tray molds stacked therein.

Abstract: Method and apparatus for sequentially delivering multiple shots of polymer material to a plurality of mold cavities to form multilayer articles. A first shot of greater than 50% of the total article weight of a first polymer material is simultaneously delivered to a plurality of mold cavities using, at each cavity, a chamber of predetermined volume that is prefilled with the first polymer material. A second shot of no greater than 10% of the total article weight of a second material is simultaneously delivered to all of the cavities beginning subsequent to the step of delivering the start of the first shot delivery step. The second shot of second material is delivered through a manifold channel that fluidly communicates with each cavity, and is injected to all cavities under pressure exerted by a source of the second material that is common to all of the plurality of cavities.

Abstract: A dry-cast concrete block molding machine for molding concrete blocks. The machine includes a weigh hopper system which senses when the proper amount of concrete, as determined by the weight thereof, has been placed in the weigh hopper to dump the weigh hopper. The machine also includes end plates in the mold box thereof which may be interchanged so that the configuration of the concrete block may be easily changed. The machine also includes a conveyor system which not only conveys mold trays into the mold box of the machine but which also is used to push the molded block outwardly from the compaction chamber of the mold box when the block has been molded.

Abstract: In one aspect, the present invention features a machine for the production of a solid dosage form wherein the machine is adapted to form a dosage form between a first forming tool and a second forming tool within a forming cavity and wherein the first RF electrode and the second RF electrode are arranged within the machine such that when RF energy is applied between the first RF electrode and the second RF electrode, the RF energy passes through the portion of the forming cavity adapted to form the dosage form.

Abstract: A control and actuation system is provided for a molding machine for producing expanded-grain cakes. The system includes a control unit, a temperature-regulated heating system, multiple motors operated by the control unit for separately actuating mechanical functions, multiple sensors for providing grain level and mechanism positional data to the control unit, control inputs for programming and otherwise providing input to the control unit, and a display device allowing the control unit to provide operational status information. The control unit regulates the thermal energy input to the mold, the molding cycle frequency, and the size of the grain charge. Several interrupts are used to ensure conformance to the control parameters and to enhance operator safety.

Abstract: The particle size distribution of a first fly ash is compared to an ideal particle size distribution that was empirically developed to provide a resin melt with a lower viscosity as more fly ash is added. A second fly ash material is similarly compared to the ideal curve and then is blended or optimized to provide an optimum filler for use with a suitable resin or similar material. Additional fly ash materials may be similarly compared and blended. Additional additives may be added for, among other things, foaming and coloration.

Abstract: A dry-cast concrete block molding machine for molding concrete blocks. The machine includes a weigh hopper system which senses when the proper amount of concrete, as determined by the weight thereof, has been placed in the weigh hopper to dump the weigh hopper. The machine also includes end plates in the mold box thereof which may be interchanged so that the configuration of the concrete block may be easily changed. The machine also includes a conveyor system which not only conveys mold trays into the mold box of the machine but which also is used to push the molded block outwardly from the compaction chamber of the mold box when the block has been molded.

Abstract: A process for continuously producing an elastomeric composition includes the step of dosing into at least one extruder at least one ingredient by means of a dosing device, wherein the dosing step is regulated on the basis of: i) actual weight values of the at least one ingredient measured at dosing instants of an evaluation time period of predetermined duration preceding a given dosing instant; ii) expected weight values of the at least one ingredient calculated for corresponding dosing instants of the evaluation time period of predetermined duration preceding the dosing instant; and iii) expected weight values of the at least one ingredient calculated for a prediction time period of predetermined duration following the dosing instant; so as to minimize a prediction weight error between actual weight values measured during the prediction time period and the expected weight values calculated for the prediction time period, and a model weight error between actual weight values measured during the prediction tim

Abstract: The invention relates to a method of pressing pressing-material mats during the production of wood-material panels in a continuous press, wherein the continuous press has upper and lower heating plates, upper and lower entry plates, which project on the entry side and form an entry mouth, and, in the upper and lower parts of the press, endlessly circulating steel pressing belts which, with the interposition of rolling bars, are supported on the entry plates and the heating plates, wherein the height h0 of the entry gap and, possibly, the entry contour of the entry mouth are set, and wherein a pressing-material mat, which is produced, and possibly pretreated, in a spreading station arranged upstream of the press, is introduced into the continuous press and pressed therein. This method is characterized in that the entry-gap height is checked, set and/or regulated in dependence on the density and/or the weight per unit area of the pressing-material mat.

Abstract: A method and apparatus for discharging a dose of castable building material into a mold include introducing a supply of castable building material into a hopper. The castable building material in the hopper is spread evenly within the hopper. A mold configured to form a molded building product is positioned beneath the hopper, and the castable building material is discharged from the hopper into the mold. In one embodiment a discharge gate is configured to discharge the castable building material evenly into the mold while substantially reducing the need for lateral movement of the castable building material in the mold.

Abstract: A control unit for a powder material compression molding machine including a powder material compressor which compresses a powder material filled between compressing members in an adjusted filled amount by making the compressing members approach to each other at a predetermined interval, so as to mold a molded product, and a pressure detector which detects a powder material compressing pressure by the powder material compressor. The control unit including a weight determiner which determines that the weight of filled powder material is normal, a thickness determiner which determines that the thickness of the molded product is abnormal in the case where the pressure detected by the pressure detector falls out of a first predetermined range when the weight determiner determines normality, and a compression controller which controls the powder material compressor when the thickness determiner determines abnormality.

Abstract: Provided are a method, an apparatus and a computer program for filling a liquid material, which do not require complicated parameter calculation and which are practiced with easier control. In the method for filling a gap between a substrate and a work placed thereon with the liquid material discharged from a discharge unit by utilizing a capillary action, the method is characterized in forming an application pattern made up of a temporarily stopping point and a non-stopping region along an outer periphery of the work, and correcting a discharge amount of the liquid material by increasing or reducing a time during which the discharge unit is stopped at the temporarily stopping point. The apparatus and the program for carrying out the method are also provided.

Abstract: A method for controlling a tablet press comprises the steps of consecutively supplying material into each die of a die table 1, subjecting the material to a pre-compression and a main-compression, whereby the main-compression is performed under substantially constant compression force and variable resulting tablet thickness of the individual tablets, and measuring a weight value representative of the weight of the material fed into the die. The quantity of material supplied to each die is regulated on the basis of a deviation between a previously measured weight value and a first set value. The weight value is measured during pre-compression of the material located in each die. A rotary tablet press is also disclosed.

Abstract: In an apparatus which has a kneading part for performing kneading of a material and an injecting part for performing injection of the material for injection molding with the kneaded material and in which the kneading part and the injecting part are connected together, a weighing screw channel portion for weighing the material and a retention screw channel portion that is formed adjacently to the weighing screw channel portion with its channel shape made different and forms a material retention space for retaining the material fed continuously quantitatively from the kneading part are formed on the injection screw shaft. Thereby, the material fed continuously quantitatively from the kneading part can be securely retained in the injecting part where intermittent operation is a performed.

Abstract: An injection molding apparatus includes a plasticizing block that includes therein a plasticizing and force-feeding mechanism which heats and plasticizes a material and force-feeds the material while kneading it, a weighing block that is connected to the plasticizing block in close contact with it, and includes therein a weighing and feeding mechanism which weighs and feeds out the material force-fed by the plasticizing and force-feeding mechanism, a fixed die plate that includes therein an injection mechanism which injects the material weighed and fed out by the weighing and feeding mechanism into a cavity, a movable die plate that advances to and retreats from the fixed die plate and makes the cavity a substantially closed space when abutting on the fixed die plate, and a clamping housing that includes therein a movable die plate drive mechanism.

Abstract: Disclosed is a molding-system set-up process, having: (i) a receiving operation, including receiving an attribute associated with a molded part, (ii) a determining operation, including determining a molding-system set-up parameter based on the attribute associated with the receiving operation, the molding-system set-up parameter being usable for setting up a molding-system operation, and (iii) a providing operation, including providing the molding-system set-up parameter.

Abstract: The invention relates to a method and a device for continuous production of a number of articles including at least two different types of articles from a pasty mass. The mass is introduced into a processor unit (4) by means of a supply unit (2), processed in the processor unit and transported further thereby, whereupon an adjunct is added by a metering unit (10) to the mass transported through the processor unit (4). The mixing of the adjunct introduced to the mass is carried out by a mixing unit (6) with mixing elements located downstream of the processor unit (4). The mass with provided adjunct is formed by a forming unit (S) into individual articles downstream of the mixing unit. According to the invention, the metering of the adjunct is carried out in a sequence of metering conditions with at least two different metering conditions, wherein the metering unit (10), for a given metering condition, introduces the adjunct to the mass at a given metering rate.

Abstract: Method for the automatic control of the amount of active ingredient of tablets during the production in a rotary tablet press, which has a die table with die bores, upper and lower punches assigned to the die bores, a filling station, a metering cam for the lower punches in the filling station, at least one pressing station with at least one upper and one lower pressing roller, wherein at least the lower pressing roller is adjustable with respect to the other pressing roller by means of a pressing roller adjustment equipment, a metering cam adjustment equipment for height adjustment of the metering cam, a compression force measuring equipment at the pressing station, a control and operating computer and an active ingredient measuring equipment, characterized by the following procedural steps: during the tablet production, the amount of active ingredient of tablets is measured and values for the amount of active ingredient are compared with a predetermined desired active ingredient value in the control and ope

Abstract: An injection nozzle is provided having a nozzle body, defining an inlet channel, an outlet channel and a connecting channel therebetween for communicating a working fluid into and out of the nozzle body. A shut-off pin is slidably mounted within the nozzle body and having a spigot mounted thereto. The shut-off pin is movable between a closed position, where the working fluid is substantially blocked from moving from the inlet channel to the outlet channel, and an open position where the spigot is withdrawn, unblocking the working fluid from moving from the inlet channel to the outlet channel. An actuator is operably connected to the shut-off pin to move the shut-off pin from the open position to the closed position. Moving the shut-off pin from the open position to the closed position generates a region of low pressure in the working fluid in the portion of working fluid trailing the spigot.

Abstract: A system and method for manufacturing composite material components having substantially uniform properties comprising means to control the metering of constituent composite material components during manufacture. The resulting composite material components may, for example, be used in the construction of decking systems, railing, porches, fences, stairs, or other similar or suitable applications that may benefit from aesthetically pleasing appearances.

Abstract: A device (1) for manufacturing a three-dimensional object by a layer wise solidification of a building material at positions in the respective layers that correspond to the object is provided. A feed (96) that supplies the building material to a building space (10) in the device (1) and at least two filler portions (98a, 98b) that are provided at the feed (96) and are independent from one another are provided, wherein one connector (99a, 99b) is provided for each building material supply container (100a, 100b) in order to supply the building material from outside of the device (1).

Abstract: An apparatus for supporting a worker involved in operating an injection-molding machine includes a neural network in which a prediction function is determined based on test molding. The worker enters a portion of a plurality of molding conditions in the form of a fixed value using a first input apparatus, thereby obtaining a relational graph of the remaining portion of the plurality of molding conditions and the predicted quality value in which the quality of a molded article is predicted.

Abstract: An apparatus and method for continuously producing constant weight portions of semi-solid matter, such as bread dough, from a large mass through a dividing mechanism whereby portions are formed on a receptacle which receives the portion so that an accurate weight indication of the portion can be taken. By separating portions of the mass with the divider, when the weight of the mass on the receptacle reaches a predetermined shutoff weight, constant weight portions are achieved. A drive motor may power the receptacle through a selectively disengageable motor drive connection, which can be disengaged to allow accurate weight indications. Variations in the weight of portions from a target portion weight may be minimized by automatically adjusting the shutoff weight at which the portion is separated by the dividing mechanism, according to the difference between the portion weight and the target weight.

Abstract: A method and apparatus are disclosed for slip-form casting a concrete product, the product being made from at least two different grades of concrete so that the concrete mix grade can be changed in an uninterrupted fashion during casting at a desired point along the length of the casting bed.

Abstract: A method is disclosed for casting a concrete product using two or more different grades of concrete mix, in which method predetermined amounts of different grades of concrete mix are delivered at appropriate instants into the feeder hopper of the slip-form casting machine.

Abstract: A molded product is produced with a desired cross-sectional area, tension of the molded product to be taken in a press-bonding device is stabilized, and the difference between the production speed of the molded body and the taking-in speed of the molded body in the press-bonding device is absorbed to improve the yield.

Abstract: A dough portion control machine for flour and similar materials comprises a dough feeding hopper, a dough extrusion apparatus including first and second a interchangeable dough distributors, a dough weight and dimension apparatus, a dough cutting apparatus, and a extrusion portion control apparatus. The first dough distributor is adapted to cooperate with the dough cutting apparatus and the extrusion dough portion control apparatus to produce dough portions in the range of 0.1-0.7 lb. and the second dough distributor, when interchanged with the first dough distributor, is adapted to cooperate with the dough cutting apparatus and the extrusion dough portion control apparatus to produce dough portions in range of 0.7-1.5 lb. and even heavier.

Abstract: An apparatus for supplying food dough forms blocks of food dough that are continuously supplied into a sheet or belt of food dough and then divides it into chunks of food dough that have preset weights.

Abstract: A spreading station for spreading chip or fiber panels, includes a dosing belt scale (2) to provided between a dosing hopper (1) and a spreading head (3). The dosing belt scale (2) is connected to a regulating unit (4, 22) with which the conveying rate (kg/s) of the chip or fiber material on the dosing belt scale (2) is gravimetrically regulatable based on a prescribed fleece weight or a prescribed nominal conveying rate that is to be achieved.

Abstract: An apparatus for supplying food dough forms blocks of food dough that are continuously supplied into a sheet or belt of food dough and then divides it into chunks of food dough that have preset weights.

Abstract: The invention provides a blowing agent delivery system and method for introducing a blowing agent into a polymeric foam processing system. The delivery system is designed to introduce blowing agent into polymeric material within an extruder when polymeric material is being plasticated, for example, during the plastication period of an injection molding cycle. The rate of introduction of blowing agent into polymeric material may be coupled to the flow rate of polymeric material in the extruder to ensure precise control over blowing agent percentage in the resulting mixture of polymeric material and blowing agent. The delivery system is also designed to prevent the introduction of blowing agent into the polymeric material when polymeric material is not being plasticated, for example, during the injection period of an injection molding cycle. The delivery system may be used in conjunction with discontinuous systems including injection molding or blow molding systems.

Abstract: A control method for an injection molding machine comprises the steps of measuring a density of a molten resin in a heating cylinder, controlling a stroke of an injection screw in an injection process by feed forward control based on the measuring step, and controlling an operating parameter of the injection molding machine based upon the measuring step.

Abstract: An apparatus for supplying food dough forms blocks of food dough that are continuously supplied into a sheet or belt of food dough and then divides it into chunks of food dough that have preset weights.

Abstract: Improved, high-capacity processing systems including a processing device such as an extruder (26) or a pellet mill (P) are provided which minimize product losses and permit the user to conduct multiple, segregated short runs with a minimum of down time between runs. The extruder systems (20, 220) include an extruder assembly (21, 221) having a special, multiple-position die assembly (28), as well as an upstream preconditioner (24) and feed bin assembly (22). A variable speed, variable output discharge screw feeder (78) is located between the preconditioner outlet (62) and extruder barrel inlet (90). A PLC-type controller (30) coupled to the extruder assembly components establishes a choke full condition at the discharge feeder (78) so that continuous uninterrupted flow of preconditioned material to the extruder (26) at a uniform mass flow rate is maintained for as long as possible.

Abstract: Filler, processing fluid and silicone polymer are controllably compounded into homogeneous filled heat cured rubber compositions with requisite reinforcing properties and levels of volatiles. In the process, a continuous feed of a silicone polymer to a compounding apparatus is monitored and a signal is generated in accordance with the monitored rate of feed. Rate of feed of filler and additives to the compounding apparatus are then adjusted in accordance with the signal.

Abstract: A resin extrusion apparatus having a weighing device (11) connected to a controller (18). A powder container (12) for supplying a powder (Y) to a resin extruder (20), a screw (13), and a motor (14) are installed over the weighing device 11. The motor (14) rotates a powder feeder (10) in proportion to a frequency of an inverter (17) connected to the controller (18). The powder feeder (10) is installed on the resin extruder (20). The powder feeder (10) supplies the powder (Y) to the resin extruder (20) quantitatively by a feedback control that is executed at regular intervals. The resin extruder (20) heats and kneads the powder (Y) and a resin (X) supplied thereto from a hopper (21) to form a resin pellet P containing the powder (Y) and the resin (X) mixed uniformly with each other.

Abstract: Improved, high-capacity processing systems including a processing device such as an extruder (26) or a pellet mill (P) are provided which minimize product losses and permit the user to conduct multiple, segregated short runs with a minimum of down time between runs. The extruder systems (20, 220) include an extruder assembly (21, 221) having a special, multiple-position die assembly (28), as well as an upstream preconditioner (24) and feed bin assembly (22). A variable speed, variable output discharge screw feeder (78) is located between the preconditioner outlet (62) and extruder barrel inlet (90). A PLC-type controller (30) coupled to the extruder assembly components establishes a choke full condition at the discharge feeder (78) so that continuous uninterrupted flow of preconditioned material to the extruder (26) at a uniform mass flow rate is maintained for as long as possible.

Abstract: Improved, high-capacity extrusion systems (20, 220) are provided which minimize product losses and permit the user to conduct multiple, segregated short extrusion runs with a minimum of down time between runs. The systems (20, 220) include an extruder assembly (21, 221) having a special, multiple-position die assembly (28), as well as an upstream preconditioner (24) and feed bin assembly (22). A variable speed, variable output discharge screw feeder (78) is located between the preconditioner outlet (62) and extruder barrel inlet (90). A PLC-type controller (30) coupled to the extruder assembly components establishes a choke full condition at the discharge feeder (78) so that continuous uninterrupted flow of preconditioned material to the extruder (26) at a uniform mass flow rate is maintained for as long as possible. In preferred forms, load cells (46, 72) are operatively coupled to the bin assembly (22) and preconditioner (24) so as to monitor material flow through the systems (20, 220).

Abstract: The present invention provides a method and apparatus for providing zero-defect pressed articles with minimal, remote operator intervention. The apparatus includes a programmable logic controller, controlling a powder feeder portion having a dump bucket which is weighed by an electronic scale. Desired weights of powder in the dump bucket are dumped to a first location and conveyed to the press. Non-desired weights of powder in the dump bucket are dumped to a second location and may be recycled. The invention provides for precise weighing of powder and avoids waste of powder in the event of improper powder dispensing and provides for complete automatic logging of production and testing data, and rejection of defective articles, avoiding the need to manually test each produced article. This method and apparatus are particularly useful in the pressing of energetic materials into pellets or casings, where manual operations are restricted for safety reasons.

Abstract: An installation for producing a three-dimensional shaped plastic foam part, comprises a plurality of tanks respectively receiving plastic foam granules and a liquid primary material, a device for reducing the plastic foam granules to a predetermined size, conduits connecting the reducing device to respective tanks receiving the plastic foam granules, a weighing tank having an inlet arranged to receive the plastic foam granules from the reducing device and an outlet, a device for mixing the plastic foam granules with the liquid primary material, further conduits connecting the mixing device to respective tanks receiving the liquid primary material and to the outlet of the reducing device, an intermediate storage tank comprising a weighing device and arranged to receive the plastic foam granules mixed with the liquid primary material, a mold having a mold cavity, and a supply line connecting the intermediate storage tank to the mold cavity, the supply line comprising a conveying device having an inlet and a con

Abstract: A dough divider is operable within a mixer bowl to divide the dough into preset weights (e.g., for bread, loaves, buns). A pendulum assembly has a retractable divider to cut a charge of dough, which is compressed by a piston. The charge of dough is expelled into a scaling die cylinder and causes a scaling die piston to be retracted until a preset weight of dough is in the scaling die cylinder. As the divider moves out of alignment with the scaling die cylinder, any excess dough is cut off and the preset weight of dough is then expelled by the scaling die piston.

Abstract: A system is provided for automatically and continuously producing chewing gum and/or chewing gum base. A system controller receives inputs of parameters necessary for production. Ingredients are automatically and continuously fed and mixed to form a desired end product. During production of chewing gum, the gum is automatically and continuously discharged from the mixer and can be automatically dusted, rolled, scored and wrapped. The system is continuously monitored with appropriate sensing devices. Signals indicative of the sensed conditions are sent to the controller, and the system automatically adjusts to produce a consistent end product. An alarm is activated upon sensing of a predetermined condition.

Abstract: A mold material introducing apparatus for introducing mold materials into a mold includes material supplying means for supplying a predetermined amount of mold material into the mold, moving means for moving the mold relative to the material supplying means and vice versa, and control means for outputting command signals to those means. The control means divides the inside of the mold into segments and assigns addresses to those segments, and controls the material supplying means and the moving means so that a predetermined amount of a predetermined mold material is located at each of the address locations. Accordingly, the mold materials of different kinds that are led into the mold are dispersed in a predetermined state.

Abstract: A method and apparatus are provided which can automatically and securely supply a molding machine with natural resin pellets and masterbatch pellets at a predetermined mixture ratio, and which is excellent in performance and costs. A natural resin feeder and a masterbatch feeder are connected to a chute of the molding machine via respective tubes. The amount of the natural resin pellets and the amount of the masterbatch pellets which are air-transferred through the respective tubes are controlled such that they are transferred in accordance with the predetermined mixture ratio. The chute and the raw material supply port of the molding machine is connected by a pipe whose cross-sectional area at the upper portion is substantially equal to or smaller than that at the lower portion thereof. The natural resin feeder and the masterbatch feeder are intermittently operated in accordance with signals from an upper limit level meter and a lower limit level meter provided on the pipe.