CA2001944C - Continuous molding apparatus and method and product therefrom - Google Patents

Abstract

Continuous molding apparatus includes a raw material supplying portion, a molding portion, a supporting portion, a mixing portion and a control portion. Each reservoir of the raw material supplying portion is connected independently with the mixing portion. The molding portion includes a plurality of spaced mold assemblies each with at least two separable mold sections. The supporting portion includes a plurality of the spaced mold assemblies each supported for independent rotation about more than one axis. The mixing portion includes an elongated mixing chamber disposed adjacent each mold assembly each with a plurality of deflector sections.
A continuous method of molding a foamed product includes providing a plurality of raw material reservoirs and continuously moving raw material from each reservoir independently to a plurality of spaced mixing chambers each of which is located adjacent to an individual mall assembly including separable mold sections. The raw materials are introduced into the mixing chambers and pass a freshly formed mixture flowing therefrom directly into a cavity of the adjacent mold assembly. Each mold assembly is rotated about more than one axis to flow the mixture over all surfaces of the mold cavity.
The rotational movement of the mold assembly is continued while the mixture forms a foam. The delivery of raw materials to each mixing chamber and the mixture flowing therefrom and the multiple axis rotation of each mold assembly is monitored.
Also, the molded product produced by the method and apparatus.

Description

CONTINUOUS MOLDING APPARATUS AND
METHOD AND PRODUCT THEREFROM
This invention relates to a novel molding apparatus and method and to the novel resulting molded product produced therefrom.
Throughout history, an important activity has been the construction of buildings for various purposes such as dwellings, storage and the like. With primitive so-cieties, it was common to construct such buildings from natural materials that were readily available. In for-ested areas, structures were erected with logs or boards that had been cut from the logs.
Where trees were less common, people used stone for building materials or artificial adobe substitutes formed from mud baked in the sun. To make artificial stones or bricks more durable and less likely to crum-ble, it was customary to mix straw or similar materials with the mud. These are believed to be the first rein-forced products.

As civilizations developed, the use of reinforced products has become much more common. For example, con-crete is formed from mixtures of cement and aggregates such as sand, crushed stone, rocks, etc. In addition, for greater strength metal rods, mesh fabric and the like may be incorporated therein. Wood products of this type include plywood and similar laminated units as well as particle board, wafer board and the like.
With the discovery of man-made polymers and resin-ous materials, the use of fillers and reinforcing mate-rials therein has become common. These materials may be in a variety of forms including particles, fibers, rods, fabrics and the like.
One of the major problems is the proper incorpor-ation of the reinforcing and/or filler materials into the continuous phase or matrix. Unless a high degree of care is exercised when the materials are combined with the principal component, they may be distributed non-uniformly and/or voids, bubbles and other weak spots may be created.
Even with fillers and reinforcing materials which can be properly placed within a matrix easily, there still is the problem of achieving uniformity of the com-position of the matrix. For example, concrete mixes which include cement, water and an aggregate can become non-homogeneous simply by settling on standing. As a result, the trucks which deliver such mixes include drums that are rotated continuously in an attempt to maintain uniformity.

This problem of non-uniformity is significant in most batch processes. Although the obvious solution to the shortcomings of batch processes is continuous processing, most products still are produced on a batch or unit basis even though it might be a continuous batch process, that is, individual units or batches are fab-ricated on an assembly line.
Examples of widespread batch processing are found in the construction industry. Buildings commonly are constructed on the site. Materials such as wood, bricks, metal beams, etc. are brought to the building site and assembled. A few components such as windows, doors, etc. may be assembled at another site. Although some manufactured housing is pre-fabricated in modules and trucked to the site for assembly, the fabrication work of such components probably still is accomplished on a unit by unit basis. As a result, reproducable high quality remains a serious problem.
The production of man-made plastics and resins is an industry that utilizes a high degree of continu-ous processing. However, for units of appreciable size, batch processing still is the rule rather than the ex-ception. For example, in the production of fiberglass structures such as boats, it is customary to construct the hulls by hand, building on an open mold in which a plurality of resin and fiberglass layers are sequen-tially laminated or a plurality of mixed resin/chopped fiber coatings are applied over the mold.

Such hand built products require a large amount of labor and supervision to insure that a reasonable level of quality is achieved. This greatly increases the cost of the product.
The problems of batch processing become more com-plicated when the resins or polymers are foam-forming.
As a multi-component mixture is placed into an open mold, the first part of the mixture begins to foam and grow from the bottom of the mold as a result of an exother-mic chemical reaction. The bubble size of the foam is smallest at the bottom where the reaction begins and is largest at the top of the mold as the reaction draws to completion. The resulting product is non-uniform in density from top to bottom and thus has poor struc-tural strength and is unsatisfactory.
In view of the above discussion, it is clear that present manufacturing and fabricating methods and pro-cedures do not provide the operating efficiencies and design possibilities required currently and in the fu-ture. Thus, there is a need for a new fabrication meth-od and apparatus which provide a high degree of quality and uniformity at a relatively low cost.
The present invention provides a novel continuous molding apparatus and method which not only overcome the deficiencies of present technology but also provide features and advantages not found in earlier expedients.
The continuous molding apparatus and method of the in-vention provide a novel uniform quality product contin-uously and at low cost.

The continuous molding apparatus of the present invention is simple in design and can be produced rela-tively inexpensively. Commercially available materials and components can be utilized in the manufacture of the apparatus. Conventional metal fabricating procedures can be employed by semi-skilled labor in the manufacture of the apparatus. The apparatus is durable in construc-tion and has a long useful life with a minimum of main-tenance.
The apparatus and method of the invention can be modified to mold a wide variety of nevr structures. Var-iations both in product composition and configuration can be attained simply and quickly with the apparatus and method of the invention. Even with such variations, uniformity and quality of product dimensions and compo-sition are still maintained vrithout difficulty.
These and other benefits and advantages of the novel continuous molding apparatus, method and product of the present invention will be apparent from the fol-lowing description and the accompanying drawings in which:
Figure 1 is a view in perspective of one form of continuous molding apparatus of the invention;
Figure 2 is an enlarged sectional view of one form of mold assembly of the molding apparatus shown in Fig-ure 1 taken along line 2 - 2 thereof;

Figure 3 is an enlarged view partially in section of another mold assembly of the molding apparatus shown in Figure 1 taken along line 3 - 3 thereof;
Figure 4 is a further enlarged fragmentary side view of the mold assembly shown in Figure 2;
Figure 5 is an enlarged fragmentary sectional view of one form of mixing portion of the molding apparatus shown in Figure 1 taken along line 5 - 5 thereof;
Figure 6 is a schematic illustration of one form of control portion of the molding apparatus of the in-vention;
Figure ~ is an enlarged fragmentary cross-sectional view of a molded product of the invention; and Figure 8 is a further enlarged fragmentary cross-sectional view of the molded product of the invention shown in Figure ~.
As shown in the drawings, one form of continuous molding apparatus 11 of the present invention includes a raw material supplying portion 13, a molding portion 14, a supporting portion 15, a mixing portion 16 and a control portion 1?.
The raw material supplying portion 13 of the mold-ing apparatus 11 of the invention includes a plurality of reservoirs 20, 21, 22, 23, 24 and 25. These reservoirs may include storage chambers for resin-forming materials, fillers, reinforcements, colors, catalysts, foam-forming materials, other additives, inert mixtures thereof and the like. Reservoirs 24 and 25 are connected with res-ervoir 20 for premixing of inert materials therein prior to transfer to the mixing portion.
Reservoirs 20 - 23 of the raw material supplying portion 13 are independently connected to the mixing portion 16 through conduit means 26, 27, 28 and 29.
Advantageously, separate bypass return conduit means 30 extend from one end of each conduit 26 - 29 adjacent the mixing portion back to the respective reservoir 20 -23 as illustrated in Figure 6.
The molding portion 14 of the molding apparatus 11 includes a plurality of spaced mold assemblies 31, 32, 33, 34 and 35. Each of the mold assemblies includes at least two separable mold sections shown for mold as-sembly 31 as mold sections 3~ and 38. The molding por-tion also includes mold section orienting means 39.
The means 39 advantageously includes a frame assembly 40 and mold section holding members 41 and 42. Prefer-ably, the mold section orienting means includes mechan-isms such as pressurized fluid activating means shown as pistons 43 and 44.
The mold sections of the mold assemblies 31 - 35 advantageously include a plurality of closely spaced movable mold segment members 46 and 4'7 providing changes in the configuration of the mold cavity formed by the -?-mold sections. As shown in Figure 4, one form of the mold segment members is actuated through a rod assembly 49 that includes a first rod 50 extending outwardly from the mold segment member 46 through a first stop section 52. On the opposite side of first stop section from the mold segment member 46, coil spring 48 is disposed on the first rod. The spring has one end 53 affixed to rod 50 along its length and an opposite free end 54 that bears against a second stop section 55 spaced from the first stop section 52.
An end 51 of rod 50 remote from the mold segment member is operatively connected to an end 56 of a second axially alibned movable rod 5~ through a connector 58.
Rod 5~ is a part of actuating means 59 which may include a piston/cylinder combination 60 or a solenoid of as shown with adjacent mold segment member 4'7. The opera-tion of the actuating means 59 advantageously is coordi-nated through the control portion 1~.
Figure 3 illustrates continuous flexible cavity liners 52 and 63 disposed over the outer faces of the assembly of mold segment members 64 and 65 similar to members 4o and 4'7 described above. This construction provides a smooth cavity surface without abrupt changes.
The flexible liners preferably are formed of a resilient material such as a silicone polymer, a fluorinated ethy-lene polymer and the like.
Advantageously, greater adaptability can be achieved with mold segment members that are replaceable easily _g_ such as by threading them off or onto the respective rod. In this way, the same mold assemblies 31 - 35 can be utilized to mold a wide variety of different molded products simply and quickly with a minimum of downtime.
Thus, the productive capacity and operating efficiency of the apparatus 11 are superior to conventional mold-ing apparatus that require the fabrication of a complete-ly new mold assembly for each change in the product being molded.
The supporting portion 15 of the molding apparatus 11 of the present invention includes a common rotatable frame section 67 for a plurality of spaced mold assem-blies. Support means 68, E9, 7~ and 71 are spaced along the supporting portion for independent rotation of each mold assembly about more than one axis.
Advantageously, mold assemblies are disposed on the supporting portion 15 generally parallel to one an-other with adjacent ends thereof in the same general transverse plane. The rotational capability of the mold assemblies preferably is about axes generally perpendi-cular to one another. The frame section 67 advantageous-ly is rotatable about a horizontal axis. The support-ing portion preferably includes a plurality of frame sections 73, 74, 75 and 76 rotatable about separate axes jointly rotatable about a common axis as shown in Fig-ure 1.
The mixing portion 16 of the molding apparatus 11 includes an elongated mixing chamber disposed adjacent each mold assembly. A plurality of deflector sections 78 and ~9 are disposed within each mixing chamber and spaced along the length thereof. As shown in Figure 1, mixing chambers 80 - 84 advantageously are located at the inlet 85 of each mold assembly 31 - 35. Preferably, the mixing chambers of the mixing portion are integrally formed with the mold assemblies as shoran in Figure 5.
The deflector sections ~l8 and ~9 disposed within the mixing chambers 80 - 84 advantageously are angled with respect to a longitudinal axis of a mixing chamber.
Preferably, the deflector sections are movable selective-ly to a position outside the mixing chamber. It is ad-vantageous that the mixing portion include cleaning means 86 movable into a mixing chamber when the deflector sec-tions are outside the mixing chamber. Preferably, the cleaning means includes a piston member 8~ that is in-serted into the mixing chamber. For complex mold designs including one or more elongated and/or tortuous areas, it is desirable that the mold assemblies include more than one inlet for controllable delivery of the moldable mixture into different zones of the mold cavity.
The control portion 1~ of the molding apparatus 11 of the present invention includes a plurality of pumps, valves, sensors, monitors and the like. Advantageously, a pump 90, 91, 92 or 93, a valve 95, 96, 9~ or 98, and a flow monitor 100, 101, 102 or 103 are located along the length of each conduit 26 - 29 that extends between the raw material reservoirs 20 - 23 and the mixing cham-bers 80 - 84.

Also, the control portion includes a plurality of drive means. A first drive 105 provides rotation of each mold assembly 31 - 35. A second drive 106 provides rotation of the frame section 6'7 therefor along a second axis. A third drive 107 provides movement of the mold orienting means 39.
The control portion 17 further includes program-mable memory means 108 and actuating means 109 responsive thereto, advantageously in combination with coordinating means 110 to control the operation of the pumps, valves and drives. Preferably, the coordinating means includes a process controller 111 that initiates changes in the flows of materials and speeds of drives to bring vari-ations therein back to the rates specified in the pro-grams present in the memory 108.
This coordination commonly is achieved through the transmission of information such as digital pulses from the monitors and/or sensors at the control compo-nents to the process controller. The operating informa-tion is compared with the preselected programming par-ameters stored in the memory. If differences are detec-ted, instructions from the controller change the oper-ation of the components to restore the molding operation to the preselected processing specifications.
The drive means of the control portion preferably include electrical motors. The control portion advan-tageously also includes means 112 in the mold assemblies monitoring the flow distribution within the mold cavities.

Novel molded products of the present invention may be formed using the molding apparatus 11 shown in the drawings employing the following steps of the mold-ing method of the invention. With the design of the desired molded product established, the control portion 1'7 including memory 108 which may be a computer, is pro-grammed with the necessary processing parameters for the particular product being molded.
The molding portion 14 is prepared to provide a mold cavity with the desired configuration. This can be accomplished by fabricating the required mold sections in the conventional manner. More advantageously, the control portion 1~ can form the mold cavity configura-tion by activating the appropriate actuating means 59 and thereby moving the mold segment members 4G and 4~
into positions providing the desired mold cavity config-uration. In this way, the configuration is created sim-ply and quickly without removing the mold sections or mold assembly from the molding apparatus 11 so downtime is greatly reduced.
To start the operation of the molding apparatus 11, buttons and/or switches 113 of a control panel 114 are depressed to activate the memory 108 and the other components of the control portion 1'7. The coordinating means 110 energizes the third drive 10'7 for actuating the mold orienting means 39 to lock the mold sections together and the first drive 105 for rotation of each mold assembly 31 - 35.

Also, the pumps 90 - 93, the valves 95 - 98 and the flow monitors 100 - 103 are energized by the coordinating means 110 in the preselected sequences of the program stored in the memory. This causes the raw materials in reservoirs 20 - 23 to advance along the conduits 26 -29 toward the mixing portion 16. For example, to mold a product including a foamed polyurethane resin, reser-voir 20 may contain a previously prepared mixture of an isocyanate and gravel as a filler, reservoir 21 a polyol, 22 foam forming materials and 23 and other reservoirs -colors, catalysts, etc. as required.
To produce high quality molded products of the invention, it is important that the raw materials deliv-ered to the mixing chambers 80 - 84 be uniform in volume and composition. This can be facilitated by providing a continuous flow of raw materials to the mixing portion and the immediate transfer of the mixture therefrom into the mold cavities. However, the volume of the mixture delivered into the mold cavities will vary depending upon the particular incremental area of the cavity being coated at any instant. Also, the delivery will be ter-minated completely when a molded product is being removed from the mold assembly.
Advantageously, as shown in Figure 6, a separate bypass conduit 30 is utilized from the end of each con-duit 26 - 29 at a point adjacent each mixing chamber 80 - 84 back to the respective reservoir 20 - 23. This construction provides a freshly formed uniform mixture into the mold cavities even though the distance is _13_ considerable between the reservoirs and the individual mixing chambers which are located closely adjacent or even within the mold assemblies.
The control portion 1~ coordinates the operation of the various system components so the required form-ulation can flow into the desired zones within the rotat-ing mold cavity. With the molding apparatus 11 as shown in Figure 1, the formulation is introduced into the mold cavity while the axis of the mold assembly is in the orientation shown, that is, radial of the central hor-izontal axis of the apparatus.
When the desired volume of the mixture has passed into the mold cavity, the deflector sections ~8 and are withdrawn from the mixing chamber. Then, the piston member 8~ moves forward into the mixing chamber pushing any liquid mixture remaining therein into the mold cav-ity and cleaning the mixing chamber for the molding of the next product. With the piston 8~ disposed in the mixing chamber, rotation of the secondary frame sections 73 - ~6 is begun while continuing the rotation about the transverse axis to flow the mixture over all surfaces of the mold cavity.
The rotations are controlled within the parameters stored in the memory 108. For particular molded products, the rotations about the respective axes may be contin-uous and/or intermittent at changing rates. Also, it may be desirable to provide arcuate rotation, that is, movement about an arc such as a rocking motion. Advantageously, monitors 112 within the mold assemblies inform the pro-cess controller when the mixture has f lowed over all surfaces of the mold cavity.
The components of the liquid mixture that flows over the mold interior quickly begin to react to form the thermosetting resin structure while rotational move-ment of the mold assembly continues. The mixture ini-tially spread over the mold interior forms a resin coat-ing with a high density with little or no bubble forma-tion. As the reaction rate increases due to the exother-mic reaction of the resin formation, the foam formed decreases in density.
The foam density decreases substantially uniform-ly as the spacing from the mold cavity surfaces increases.
This decrease in density continues until the foams that are expanding toward each other meet. At these boundar-ies, a thin high density central barrier is formed.
The rotation of the mold assembly is stopped and pistons 43, 44 are actuated to separate the mold sections 3~ and 38 and free the molded product therefrom. The separated molded product is set aside to complete the foam formation and/or the curing of the resin therein.
During this period, the final expansion of the foam, free of the mold's restraint, stresses the high density outer skin or layer of the product. This stressing of the skin increases the strength and puncture resistance thereof and also the structural strength of the molded product itself. The structural strength of the product can be enhanced further by including a reinforcement such as metal or fiberglass fibers in the mixture prior to molding. Also, preformed reinforcements 129 e.g. metal rods can be positioned in the mold cavity before the mold sections are closed.
Figure ~ illustrates an enlarged cross-sectional view of a molded product of the invention produced em-ploying the molding apparatus and method described above.
Figure 8 illustrates a further enlarged fragment of Fig-ure ~. As shown, the product includes high density stressed outer layers 120 and 121 with less dense layers 122 and 123 extending inwardly therefrom to a thin high density central barrier 124. Filler particles 125 and fiber reinforcements 126 are distributed throughout the pro-duct. Resin matrix 12~ surrounds individual filler par-ticles 125, fiber reinforcements 126 and gas bubbles 128.
Advantageously, the stressed outer layers 120 and 121 include a somewhat greater concentration of hard filler particles and the foamed layers 123 and 124 include a somewhat greater concentration of the fiber reinforce-ment. Thus, the present invention provides a novel mold-, ed product that is a unitary structure with integral hard outer surfaces over a more flexural strong core and includes high proportions of fillers and/or reinforce-ments.
The above description and the accompanying draw-ings show that the present invention provides a novel molding apparatus, method and product which not only -lo-overcome the deficiencies and s'nortcomings of earlier expedients, but also provide novel features and advan-tages not found in previous products, methods and appa-ratus. The molding method and apparatus of the inven-tion produce continuously a novel product with close tolerances of composition, strength and appearance at a significantly lower cost than competitive products.
The continuous molding apparatus of the invention is simple in design and relatively inexpensive. Commer-cially available materials and components can be utilized in the fabrication of the molding apparatus using con-ventional metal working techniques and procedures.
Products can be produced efficiently with the ap-paratus and method by operators with limited experience and aptitude after a short period of instruction. The apparatus is durable in construction and has a long use-ful life with a minimum of maintenance.
The apparatus and method of the invention can be utilized to mold a wide variety of different products.
Variations in composition, structure and surface appear-ance of the products can be achieved simply and quickly with the method and apparatus of the invention.
It will be apparent that various modifications can be made in the particular continuous molding appa-ratus and method and the products produced thereby as described in detail above and shown in the drawings within the scope of the present invention. The size, configuration and arrangement of components and materials can be changed to meet specific requirements. For ex-ample, the number of components and reservoirs may be different. In addition, the mold assemblies can be heated and/or cooled to control the rates at which reac-tions and foaming take place therein. Also, the appa-ratus may include other drive and actuating components and mechanisms.
These and other changes can be made in the contin-uous molding apparatus, method and products provided the functioning and operation thereof are not adversely affected. Therefore, the scope of the present invention is to be limited only by the following claims.

Claims (5)

1. Continuous molding apparatus including a raw material supplying portion, a molding portion, a supporting portion, a mixing portion and a control portion; said raw material supplying portion including a plurality of reservoirs, said reservoirs being connected independently with said mixing portion through conduit means; said molding portion including a plurality of spaced mold assemblies, each of said mold assemblies including at least two separable mold sections and mold section orienting means; said supporting portion including a common rotatable frame section for a plurality of said spaced mold assemblies, support means spaced along said supporting portion for independent rotation of each mold assembly about more than one axis, said raw material conduit means being disposed adjacent at least a part of said frame section and communicating with each mold assembly; said mixing portion including an elongated mixing chamber disposed adjacent each mold assembly, a plurality of deflector sections within each mixing chamber spaced along the leng~ thereof; said control portion including pump means, valve ~ans and flow monitoring means disposed along the length of each raw material conduit means, independent drive means for each mold assembly, for said frame section therefor, and for said mold orienting means; programmable memory means and actuating means responsive thereto respectively controlling and activating said pump means, said valve means and said drive means.

2. Continuous molding apparatus according to Claim 1 wherein said raw material supplying portion includes separate bypass return conduit means from one end of each of said conduit means adjacent said mixing portion back to the respective reservoir.

3. Continuous molding apparatus according to Claim 1 wherein said raw material conduit means communicate with said mixing chambers through said rotatable support means.

4. Continuous molding apparatus according to Claim 1 wherein said mold assemblies are disposed generally parallel to one another with adjacent ends thereof in the same general transverse plane.

5. Continuous molding apparatus according to Claim 1 wherein said rotational capability of said mold assemblies is about axes generally perpendicular to one another.
5. Continuous molding apparatus according to Claim 1 wherein said mold sections of said mold assemblies include a plurality of closely spaced mold segment members providing changes in the configuration of said mold cavity.
7. Continuous molding apparatus according to Claim 1 wherein said mold sections of said mold assemblies include flexible cavity liners including a plurality of closely spaced mold segment members bearing against same providing changes in the configuration of said mold cavity.

8. Continuous molding apparatus according to Claim 1 wherein said mold section orienting means includes pressurized fluid activating means.
9. Continuous molding apparatus according to Claim 1 wherein said frame section is rotatable about a horizontal axis.
10. Continuous molding apparatus according to Claim 1 wherein said supporting portion includes a plurality of frame sections rotatable about separate axes jointly rotatable about a common central axis.
11. Continuous molding apparatus according to Claim 1 wherein said elongated mixing chambers of said mixing portion are integrally formed with said mold assemblies.
12. Continuous molding apparatus according to Claim 1 wherein said deflector sections of said mixing portion are angled with respect to a longitudinal axis of each elongated mixing chamber.
13. Continuous molding apparatus according to Claim 1 wherein said deflector sections are movable selectively to a position outside said mixing chambers.
14. Continuous molding apparatus according to Claim 13 including cleaning means movable into said mixing chamber when said deflector sections are outside said chamber.

15. Continuous molding apparatus according to Claim 14 wherein said cleaning means includes a piston member.
16. Continuous molding apparatus according to Claim 1 wherein said control portion includes coordinating means for said memory means and said pump means, said valve means, said flow monitoring means and said drive means.
17. Continuous molding apparatus according to Claim 1 wherein said drive means of said control portion includes electrical motors.
18. Continuous molding apparatus according to Claim 1 wherein said drive means of said control portion includes pressurized fluid motors.
19. Continuous molding apparatus according to Claim 1 wherein said control portion includes monitors within said mold assemblies.

20. A continuous molding method including the steps of providing a plurality of raw material reservoirs, continuously moving raw material from each reservoir independently to a plurality of spaced mixing chambers each of which is located adjacent to an individual mold assembly including separable mold sections, introducing raw materials into said mixing chambers, passing a freshly formed mixture flowing from each mixing chamber directly into a cavity of said adjacent mold assembly, rotating each mold assembly about more than one axis, flowing said mixture over all surfaces of said mold cavity by said rotational movement, continuing said rotational movement of said mold assembly while said mixture forms a foam within said cavity thereof; monitoring the delivery of raw materials to each mixing chamber, the resulting mixture flowing therefrom and the multiple axis rotation of each mold assembly, separating said mold sections of each mold assembly after said foam has formed within said mold cavity, removing a molded foamed product from said separated mold sections, closing said mold sections and repeating said steps to form a multiplicity of such molded products on a continuing basis.
21. A continuous molding method according to Claim 20 including disposing said mold assemblies substantially parallel to one another.

22. A continuous molding method according to Claim 20 including diverting raw material to its respective reservoir prior to entering said mixing chambers, comparing the flow rates of the raw materials with preselected values and passing the raw materials continuously into said mixing chambers when the flow rates are substantially the same as the preselected values.
23. A continuous molding method according to Claim 20 including coordinating and controlling the steps of the method automatically.
24. A continuous molding method according to Claim 20 including rotating the mold assemblies about axes generally perpendicular to one another.
25. A continuous molding method according to Claim 20 including introducing a resin-forming component into said mixing chamber.
26. A continuous molding method according to Claim 20 including introducing a particulate filler into said mixing chamber.
27. A continuous molding method according to Claim 20 including introducing a fiber reinforcement into said mixing chamber.
28. A continuous molding method according to Claim 20 including introducing a foam forming component into said mixing chamber.

29. A continuous molding method according to Claim 28 including introducing a carbon dioxide foam forming component into said mixing chamber.
30. A continuous molding method according to Claim 20 including cleaning said mixing chambers prior to repeating the steps of the method.