Abstract: Process for manufacturing a golf club shaft made of composite materials, including the successive steps of fitting a tubular, flexible impermeable bladder around a rigid mandrel whose length is at least equal to the length of the shaft to be produced, dressing the mandrel with a composite structure comprising fibers impregnated with a synthetic resin matrix, placing the mandrel in the mold, and then carrying out a mold operation by applying at least one internal pressure exerted by feeding a fluid inside the bladder.

Abstract: A method for fabricating, and a resulting structure for, a seamless, reusable and collapsible mandrel suitable for forming a plurality of seamless and hollow fiber wound vessels upon is disclosed. A destructible mandrel is used to form the seamless reusable mandrel. The destructible mandrel is preferably formed from a material which can be destroyed by dissolving, for example, materials such as foam or plaster. The seamless, collapsible, and reusable mandrel includes a plurality of different layers including a gas impermeable layer, a continuous fiber wound layer, and a release surface forming the outermost layer of the seamless, collapsible, and reusable mandrel. The resulting seamless, reusable and collapsible mandrel has advantages over mandrels which include a seam. Such advantages include a longer useful life and consistently high quality fiber wound vessels at a relatively low cost.

Abstract: A bicycle frame has a seat tube fitting to which a seat is attachable, a head tube fitting to which forks are attachable, and a bottom bracket fitting to which a crank shaft is attachable. A single frame tube of fiber reinforced polymer composite interconnects the seat tube fitting, head tube fitting, and bottom bracket fitting in a manner which provides a lightweight, and durable bicycle frame. The single frame tube is formed by disposing the seat tube fitting, head tube fitting, and bottom bracket fitting within a first mold section, then disposing a bladder covered with polymer impregnated fiber within the first mold section such that the bladder passes through openings in the seat tube fitting, head tube fitting, and bottom bracket fitting. The bladder is then inflated while the polymer impregnated fiber is heated so as to form a fiber reinforced polymer composite which conforms to the shape of the cavity formed within the mold, thereby defining the desired bicycle frame.

Abstract: The present invention provides a method and apparatus for the rapid, uniform curing of cylindrical, polymeric objects. The invention provides precise, accurate control of both the curing temperature and pressure because the heating system is independent of the pressurization device. Cylindrical polymeric objects are cured by mounting the object on a cylindrical mandrel, applying substantially uniform pressure to the outer surface of the object, typically through an expandable bladder, and supplying curing is heat directly to the object by circulating a liquid heat transfer medium through the bladder or mandrel. Preferably, the expandable elastomeric bladder is mounted coaxially with the mandrel, and is expanded with a suitable liquid or gas to provide the pressure.

Abstract: Particularly large-size bell and spigot pipes of ceramic molding material are isostatically pressed within a hollow-cylindrical pressure pot with a molding cavity for the molding compound. An inner core is axially extractable and an elastomeric diaphragm is disposed concentrically around the inner core. The diaphragm is clamped in place at its end face and there is defined between the pressure pot and the diaphragm a chamber which communicates with a source of hydraulic pressure. The inner core is provided with a molding ring on which the bell region of the bell and spigot pipe is formed. The molding ring has a reduced-diameter end region and thus defines two end faces. The two end faces are concentric but axially spaced apart. At least the upper end face of the molding ring is provided with a surface coating of elastic plastic material.

Abstract: A process of molding a racket frame having an evacuation stage for shrinking a lamination of an inner bladder, a tubular prepreg and an outer protective tube before closing a mold, and the reinforcing fibers of the prepreg are not cut by inner edges of the mold, thereby preventing the racket frame from burr due to the reinforcing fibers cut by the inner edges.

Abstract: The invention is directed to a golf club shaft and to a process for manufacturing same. The golf club shaft is made of a fiber- and resin-base composite material, the shaft including, along a part of its length, a neck portion in which a ring is inserted, such ring being made of a material having a density higher than the density of the composite material and the ring having a first end portion and a second end portion each having an inner surface in contact with the surface of the neck portion which flares out gradually up to the ends of the ring.

Abstract: An apparatus and method for manufacturing a synchronous drive belt or timing belt is disclosed. The method allows a belt with axially interlocked teeth to be manufactured. The method utilizes transfer molding, as opposed to compression molding, and involves an inflatable diaphragm which pushes rubber radially outwardly from a mandrel into a mold having teeth on an inner surface. The method includes the provision of a barrier layer which can be advantageously built into the belt to improve the transfer molding process.

Abstract: A method and apparatus for masking components of a hot water tank from insulation wherein a carrier sheet containing a pair of inflatable rings is insertable into the space between the inner tank and outer shell of the hot water tank. The inflatable rings surround electrical components on the inner tank to prevent insulation injected into the space from covering the electrical components. Inflatable bags are insertable into threaded bores on fittings connected to the inner tank to prevent the insulation from covering the threaded bores, and to prevent insulation from escaping to the outside of the outer shell.

Abstract: A process for forming composite hollow crown stiffened skins and panels in which a first layer or skin is placed on a forming surface of a female mold and, after forming a plurality of U-shaped stiffener elements in the first skin, a second skin is placed over the first skin, whereupon the resulting assembly is prepared for autoclave curing. The stiffener elements are formed by pressing the first skin into U-shaped depressions in the female mold surface and inserting a hollow, expandable rubber mandrel into each of the depressions on top of the first skin. Valve stems in the mandrels enable maintaining the pressure inside at atmospheric pressure. The mandrels are maintained in their "pressurized" state during subsequent formation and autoclave curing steps.

Abstract: In charging a fluid molding material in an elastic molding die composed of a die body having an opening and a die support portion extending from the opening to the outside by pouring the molding material from the opening into time die body, the molding material in an amount of 1/5 to 3/5 of a volume of the die body is first charged, a molding material-charged portion of the die body is then crumpled or pinched, and then the entire die body is filled up with the molding material. The crumpling or pinching operation is achieved by such means as a blade shutter, pressing plates, air bags, or passing between two plates or conveyor belts, thereby charging the fluid molding material in the die body of the elastic-molding die without occurrence of air voids.

Abstract: It is unnecessary to carry out the grinding process for improving the accuracy in the inner surface configurations, dimensions and the like of the hoses around the portion to be connected to a mating member. Further, the flashes, resulting from the material leakage, are inhibited from producing during the injection molding of a connecting portion following the blow molding of a hose body. Accordingly, it is possible to obviate the deflashing and finishing process and to prevent the material shrinkage from occurring.After forming a hose body 12 with a thermoplastic resin by blow molding, the hose body 12 is set in an injection molding mold 20 including an inner mold 24 and an outer mold 22, and the inner mold 24 is adhered to the opening portion of the hose body 12 by sealing means 28, 30, 40 or 42 in a fluid-proof manner.

Abstract: A composite legal type bicycle frame is disclosed which contains a front frame portion and a rear frame portion. The front frame portion contains a central main and a plurality of legs for connecting the central main with various components of the bicycle, and the rear frame portion contains a rear fork, which consists of a left rear branch and a right rear branch. The left and right rear branches are first cured and glued together at respective abutting surfaces thereof to form an integral rear fork before they are adjoined with the front frame portion, via prepregs and using a cocuring procedure. The left and right rear branches are formed to contain cross-shaped matching protrusion and recess, respectively, on the abutting surfaces thereof, so as to enhance the integrity of the integral rear fork. As a result, a great flexibility of design options can be obtained. For example, the rear fork can be connected to one of the legs but not to the central main.

Abstract: A unitary vacuum bag for forming of a fiber reinforced composite article, made of a fabric mesh reinforced curable elastomer, having a smooth surface on both sides. The bag is constructed upon the surface of the article which is to be reproduced and upon a planar flange extension of the mold for said article. A rigid vacuum chamber assembly consisting of a planar fiber reinforced composite or equivalent sheet is sealed on the outer periphery to the mold flange extension and on the inner periphery to the top surface of the bag by rubber seals which are attached to the vacuum chamber assembly under surface. A vacuum port through the vacuum chamber assembly between the rubber seals allows vacuum to be applied to the chamber causing it to be pressed by atmospheric pressure to the mold flange extension and bag periphery thus sealing the bag to the mold periphery and simultaneously providing a continuous vacuum source around the entire periphery of the bag.

Abstract: Apparatus and methods for forming an article of advanced composites on a tool forming surface from a preform are disclosed. Apparatus includes, according a preferred embodiment, a tool forming surface, a first diaphragm for urging a preform into conforming contact with the tool forming surface, and a second diaphragm for supporting a side of the preform opposite the side engaged by the first diaphragm during forming. The second diaphragm does not extend completely between the preform and the tool forming surface. The apparatus is arranged with a first diaphragm mountable on the apparatus and conformable to a preform to be formed and a second diaphragm mounted on the apparatus and conformable to a portion of the preform simultaneously with the first diaphragm. A forming tool is provided, including a tool forming surface positionable for receiving the preform between the first diaphragm and the second diaphragm when the first and second diaphragms are mounted on the apparatus.

Abstract: An apparatus and method for manufacturing articles made of polyurethane that includes a mold assembly in communication with a mix chamber. The mix chamber is positioned below the mold assembly. The mix chamber includes a propeller for mixing the liquid polyurethane chemicals. The mix chamber further includes a pneumatically actuated bladder that causes the mixed chemicals to move from the mix chamber to the mold assembly. The chemicals expand to take on the shape of the mold. The method of the present invention comprises the steps of: (a) selecting polyurethane chemicals having certain specific weights; (b) placing said chemicals in a mix chamber wherein chemicals stratify according to their specific weights to prevent detrimental reaction among the chemicals until final mixing; and (c) allowing the chemicals to expand to form an article.

Abstract: A method is provided for installing a refractory lining in a metallurgical vessel having a main opening which is much smaller than the diameter of the vessel. The method is especially useful in a vessel having a circular or otherwise curved cross-section. A form or mold is assembled inside the vessel, leaving a space between the form and the outer shell of the vessel. The form is supported on both sides, to maintain the distance between the form and the outer shell, and to prevent collapse or implosion of the form. Then, a pumpable casting composition having a smooth and easy flow is injected between the form and the shell, and allowed to harden. The use of the pumpable composition significantly shortens the time required to form the liner.

Abstract: The bicycle frame of the invention is formed by selecting and adhesively joining previously formed and precured composite tubes to previously formed and precured composite lugs. The precured lugs are shaped from preforms comprising a plurality of resin impregnated fiber reinforced layers formed into a stacks having the fibers of adjacent layers cross one another, with preforms of each lug component being a set of shaped overlapping segments of the lug to be formed. The overlapping segments are then brought together and placed around an inflatable bladder to form an assemblage that is placed in a female mold, preferably of two halves, that are closed for forming the lug. The resulting assemblage is cured, with the bladder pressurized for urging the respective preforms to the mold shaping surfaces, providing a high laminate compaction during cure for a uniform, thin walled, strong, tubular, lug. The lugs are preferably formed with one or more plugs for closely fitting into adjacent open ends of the tubes.

Abstract: A process for producing a cylindrical product of a fiber reinforcement-thermoplastic resin composite, which involves disposing a mandrel on a flexible guide sheet which can be formed in the shape of the letter U around the mandrel, heating a fiber reinforcement-thermoplastic resin composite sheet to a temperature not lower than the distortion temperature of the resin and lower than the thermal degradation temperature of the resin of the composite, disposing an end of the heated composite sheet at a line of contact of the mandrel with the flexible guide sheet, then rolling the mandrel on the guide sheet while moving the guide sheet, the guide sheet forming a shape of the letter U around the mandrel being drawn into the concave portion of the letter U, and the composite sheet disposed between the mandrel and the guide sheet being in intimate contact with the mandrel and the guide sheet, to thereby wind the composite sheet on the mandrel, and then recovering a cylindrical product made from the wound composite sh

Abstract: Method for embodying hollow articles made of composite material including at least one access orifice via winding/laying down fibers on an expansible mandrel, the resulting articles and a recoverable and removable mandrel. The method includes placing preimpregnated fibers on an expansible, extractable mandrel having a longitudinal axis by at least one of winding and laying down the preimpregnated fibers on the mandrel, the placing of circumferential fibers of the preimpregnated fibers comprising placing the circumferential fibers at an angle to approach or reach 90.degree. with respect to the longitudinal axis and to form on the mandrel a sinuous line and/or plural, discontinuous elements, so as to enable the preimpregnated fibers to be expanded circumferentially during radial expansion of the mandrel; and expanding the mandrel inside a shaper while polymerizing the preimpregnated fibers.

Abstract: A method of molding an article of fiber reinforced material includes a step of providing a mold in the shape of the article for receiving fiber material. The mold includes a top and a bottom. A source of liquid resin located exterior of the mold is provided. The liquid resin is supplied from the source to the bottom of the mold and contacts the fiber materials. The liquid resin is allowed to wick throughout the fiber material from the bottom of the mold to the top of the mold through capillary action while the source of liquid resin is moved from the bottom of the mold to the top of the mold thereby saturating the fiber material with the liquid resin. The liquid resin is then allowed to cure, and the article is then removed from the mold.

Abstract: A platen for applying pressure during hydroforming of polycarbonate and similar sheet material includes a flexible diaphragm for applying pressure in response to hydraulic fluid under pressure within a platen cavity and a diaphragm circumscribing sealing member for inhibiting seepage of hydraulic fluid and for preventing outward migration of the material of the diaphragm during a hydroforming operation. The junction between the sealing member and the diaphragm is conforming and void free to prevent hydraulic fluid flow therebetween. To help contain the hydraulic fluid within the platen cavity, a circumscribing inwardly extending foot of the diaphragm provides a mechanical and dynamic seal against an adjacent surface of the platen cavity.

Abstract: A frame for a game racquet such as a tennis racquet is formed by winding a resin-free filament over a mandrel to form a tube, inserting the wound tube into a mold, and injecting resin into the mold.

Abstract: A composite ski pole is formed of fiber reinforced plastic laminates laid up around an inflatable bladder, and placed in a female mold. The bladder inflates to compact the laminates to substantially eliminate voids and form a smooth, hollow ski pole with a structurally strong and stiff skin. The molds may use compound shapes such as differing cross sections or longitudinal bends.

Abstract: Furniture and furniture parts are formed with support bodies of cardboard laminate. The winding is formed from a cardboard which is pressed into the appropriate shape. If desired, the winding is divided into pieces. Parts of upholstered pieces of furniture, such as armrests, backrests and seat parts can be manufactured.

Abstract: A spark plug with integral electrical components for producing a spark with an increased size and a larger resulting flame kernel in an internal combustion engine. One or more coils may be built into the spark plug for creating a magnetic field in the vicinity of the spark. This magnetic field has the effect of bending and rotating the spark in a circular motion. Also, a capacitor may be incorporated into the spark plug to increase the intensity of the spark. A method of producing such a spark plug utilizes a cermet ink applied to the ceramic spark plug insulator before the insulator is completely hardened. The cermet ink may be used to create monolithic spark plug electrodes, integrated coils and integrated capacitors. The method may also be used to crease monolithic electrically conductive paths through any solid dielectric material.

Abstract: An intraluminal stent comprising fibrin treatment of restenosis is provided by a two stage molding process.

Abstract: Lampshades are formed by fitting a lampshade blank on a mandrel of complementary shape, which mandrel also supports upper and lower metal hoops to be incorporated into the lampshade. The edges of the lampshade blank are then locally heated and deformed to surround the metal hoops. The deformation of the heated edges of the lampshade blank may advantageously be effected by surrounding the lampshade/mandrel assembly with a membrane, and forcing the membrane into contact with the assembly.

Abstract: A primary outer shell includes, in its most preferred embodiment, a base and a wall which includes at least one embedded foreign object and defines openings into an inner cavity containing a burnable candle member which causes the outer shell to glow and cast shadows without melting. The outer shell is constructed according to a unique molding method which includes at least partially immersing a swollen distensible mold, such as a water-filled balloon, into a reservoir of molding material, such as wax, to allow the molding material to form a molded shell around the distensible mold. After the distensible mold with the attached molded shell is removed from the reservoir of molding material, it is placed upon a flat surface to form a flat bottom into the molded shell.

Abstract: A two-stage co-cure method for fabricating a composite article having a box-beam cross-sectional configuration wherein an outer shell portion of the composite article is fabricated and configured in the first stage to function as the tooling for completing the fabrication of composite article in the second stage.

Abstract: An apparatus for curing a tapered airsleeve has a bladder curing chamber into which a rigid tapered sleeve cartridge is inserted to form the airsleeve thereon. The bladder curing chamber is formed by a rigid bladder support tube positioned between upper and lower plates and joined by strain rods. A straight cylindrical bladder is positioned within the bladder support tube and the ends are sealed by flipping them from the inside of the bladder support tube 180.degree. over each end of the tube for sealing the curing chamber. The hollow tapered sleeve mold or cartridge is inserted into the bladder curing chamber and will be dimensionally similar to the airsleeve to be molded therein. A preshaped uncured green sleeve is positioned over the tapered sleeve cartridge before inserting it into the curing chamber. The straight cylindrical bladder is inflated and expands radially outwardly causing the uncured sleeve to conform against the tapered sleeve cartridge.

Abstract: A platen for applying pressure during hydroforming of polycarbonate and similar sheet material includes a flexible diaphragm for applying pressure in response to hydraulic fluid under pressure within a platen cavity and a diaphragm circumscribing sealing member for inhibiting seepage of hydraulic fluid and for preventing outward migration of the material of the diaphragm during a hydroforming operation. The junction between the sealing member and the diaphragm is conforming and void free to prevent hydraulic fluid flow therebetween. To help contain the hydraulic fluid within the platen cavity, a circumscribing inwardly extending foot of the diaphragm provides a mechanical and dynamic seal against an adjacent surface of the platen cavity.

Abstract: A method for fabricating, and a resulting structure for, a seamless, reusable and collapsible mandrel suitable for forming a plurality of seamless and hollow fiber wound vessels upon is disclosed. A destructible mandrel is used to form the seamless reusable mandrel. The destructible mandrel is preferably formed from a material which can be destroyed by dissolving, for example, materials such as foam or plaster. The seamless, collapsible, and reusable mandrel includes a plurality of different layers including a gas impermeable layer, a continuous fiber wound layer, and a release surface forming the outermost layer of the seamless, collapsible, and reusable mandrel. The resulting seamless, reusable and collapsible mandrel has advantages over mandrels which include a seam. Such advantages include a longer useful life and consistently high quality fiber wound vessels at a relatively low cost.

Abstract: A description is given of an apparatus for forming and deep-drawing the neck region at the edge of a plastics half shell, having a deep-drawing tool (3) and a counter-pressure plate (2) which are movable in two directions relative to each other, wherein the deep-drawing tool (3) embraces a deep-drawing cavity (29) in shell-like manner and has a recess (30) in the side wall (31) at the edge (32). So that deformation of the collar at the edge of the plastics half shell and also over-heating of the plastics plate for forming the half shell are avoided, according to the invention it is provided that the counter-pressure plate (2) has at least one opening (16) in the contact face (17) facing the deep-drawing tool.

Abstract: A method for producing a composite golf club head includes the steps of forming a metal hollow casing; disposing a bowl-shaped laminated member in the metal hollow casing; providing an expansible pocket in the bowl-shaped laminated member, the expansible pocket containing a mixture of sodium nitrite, ammonium chloride and water; disposing a sheet of carbon fiber composite material over an open top portion of the metal hollow casing, in order to close the open top portion of the metal hollow casing and the open end of the bowl-shaped laminated member; disposing the metal hollow casing in a mold; and heating the mold to a temperature of 140.degree.-160.degree. C.

Abstract: A novel composition comprising a metal or ceramic matrix material includes a reinforcing system of hollow, similarly aligned carbon-coated ceramic fibers which provide high strength, increased creep resistance and a significant reduction in weight. Also disclosed is a novel structural component incorporating the reinforcing system of hollow fibers to provide a mechanism enabling fluids or gases to pass or be injected through the element fibers for cooling or other functions. A method for fabricating the hollow fiber-reinforced component is also disclosed. Various applications for the fiber-reinforced structural component are also disclosed.

Abstract: In a device for manufacturing composite plastic mouldings, at least two different reaction mixtures are injected simultaneously through different sprues (24,26) into the cavity (28,28',28") of a mould (20,22). During the injection time of at least one of the reaction mixture, the cavity is subdivided into two or more mutually isolated regions. Following the injection of one reaction mixture, the separation between the regions of the cavity is removed and the at least partially liquid reaction mixtures converge in the separation plane. This device makes possible to join at least two materials having different properties in a single operation. It is useful for manufacturing bumper bars, spoilers, coach-work, and internal linings of motor vehicles.

Abstract: A method of molding a composite bicycle frame that includes the steps of curing a pair of seat stays and chain stays respectively and then connecting with the front triangle. Non-foaming dilatable materials are provided at suitable locations in the mold, such as the steering support cavity, the pedal support cavity, the seat stay butting cavity and the chain stay butting cavity. By heating the mold once, the seat stays and chain stays will secure with the front triangle and the front triangle can be cured at the same time to simplify the mold and the process.

Abstract: A method for fabricating fiber reinforced resin matrix composite structures having molded outside surfaces with intermittent molded inside surfaces (e.g. an aircraft skin with internal stiffeners) is performed as follows: composite prepreg stiffener sections are preformed and laid up on the inside portion of the rigid portion of the vacuum bag and the lay-up debulked. Elastomeric tubes are then installed in rigid cavity portions of a hybrid vacuum bag and sealing wedges are forced into place to hold the elastomeric tubes and at the same time seal them to the rigid portion of the cavity. The elastomeric tubes extend through and protrude from the sealing wedges. Skin plies are then laid up on a primary mold and the hybrid bag installed on the mold. Index pins are provided to properly orient the hybrid bag to the primary mold or tool. A vacuum is then drawn on the bag, any vacuum leaks are remedied, and the part is ready for curing in either an oven or an autoclave.

Abstract: A first surface of a prepreg laminate is positioned against a female mold surface. An inflatable bladder is positioned against an opposite surface. A vacuum bag encloses the mold laminate and bag and they are placed in an autoclave. The bladder is inflated to cause the laminate to conform closely to the female mold surface.

Abstract: A method of making a condom from a precursor tubular element formed of elastic film material, having a closed distal end and an open proximal end. The precursor tubular element is placed over a tubular mandril and expanded outwardly from the mandril against a surrounding cylindrical chamber, following which the expanded precursor tubular element is deflated for subsequent condom usage.

Abstract: Using a fiber reinforced thermoplastic resin, component materials of shapes obtained by partitioning the shape of the desired hollow article into a plurality of parts are molded. Reinforcing members 5, made of a prepreg wherein reinforcing fiber is impregnated with thermoplastic resin, are affixed to the junctions of these component materials 1. These are housed within mold 7 as a hollow provisional assembly and a joined unitary body is formed by adding pressure and heating. Using the method of the present invention, it is possible to efficiently manufacture a complicatedly shaped hollow article, the obtained molded article being one which excels in mechanical strength and, moreover, has a surface which is continuous and smooth.

Abstract: A process for fabricating manufactured articles from fiberglass reinforced thermoplastic sheets, which consists of forming said plates while they are heated at their melting point and coupled with a barrier film, by either blow-moulding or thermoforming.

Abstract: The present invention pertains to the construction of modular structures used as a building blocks to create an habitation or integrated structures which form habitations. In both cases flexible molds are injected with mold materials to form the final structure created. An outer cavity of the mold is first inflated to create either a finalized shape of the structure or a partial shape for the structure. If internal constraints of the innermost cavity are already included, a finalized structural shape is obtained. If internal constraints for the innermost cavity have to be added, the final shaped is obtain after those constraints are placed within the innermost cavity.

Abstract: An elastic molding die is composed of an elastomer laminate film, of which the innermost layer is formed of an elastomer not containing fillers. The innermost layer elastomer is preferably an oil-resistant elastomer. Alternatively, an oil-repellent agent may be contained in the innermost layer elastomer. The outer layer may be formed of an elastomer containing fillers. Furthermore, an oil blocking layer can be provided between the inner layer and the outer layer. A master model is dipped in an elastomer solution not containing fillers, heat dried to form a gelled elastomer film, the film is coated with a coagulant, dipped again in an elastomer solution, taken out, gelation treated, and the elastomer film is peeled from the master model to obtain an elastic molding die. In another method, a once-formed hollow elastic molding die is turned inside out, pressed in with a gas to swell, the swollen die is coated with an elastomer solution not containing fillers, heat dried, and turned it again inside out.

Abstract: A method of making game racket frame of plastic compound material includes a tubular body, which is formed by a bendable inner tube wrapped orderly and windingly with the cured thermoplastic plastic thin films and the long fiber fabric sheets made up of a plurality of long fiber bundles. The tubular body is placed in a mold cavity of a molding tool, which is subjected to a heat corresponding to the melting point of the thermoplastic plastic thin film. A gas with a first predetermined pressure is introduced into the tubular body so as to force the molten thermoplastic plastic thin film to diffuse uniformly into the interstices of the fiber bundles. Another gas having a second predetermined pressure is introduced into the tubular body to force the outer shell of tubular body to attach intimately to the wall of mold cavity of the molding tool, which is then cooled to permit the removal of the racket frame made therein. The method produces a recyclable racket frame and no waste causing environmental pollution.

Abstract: A method of repairing a damaged (e.g., cracked) portion of a buried sewage pipe by permeating one or more layers of fibrous material with a hardenable plastic compound (such as epoxy resin), convoluting the thus obtained mat around a radially expandible length of hose to permit frictional engagement between the internal surface of the mat and the external surface of the hose, introducing the hose into a selected defective portion of the pipe, expanding the hose and the convoluted mat so that the mat engages the internal surface of the pipe, deflating the hose, and withdrawing the hose from the pipe, preferably after the plastic compound has set wherein a film of polyethylene is inserted between the external surface of the hose and the internal surface of the convoluted mat to enhance friction and to thus compel the hose to turn in the course of the expanding step.

Abstract: A method of making a bicycle frame of plastic composite material includes a process in which an inner tube is wrapped orderly with at least a thermoplastic matrix layer and a long fiber reinforcing layer, so as to form a tubular object having a laminated outer shell. The tubular object is placed in a molding tool, which is then heated up to a temperature corresponding to the melting point of the thermoplastic matrix. Under the condition that the heating temperature is maintained, a pressurized gas having a pressure is introduced into the tubular object in such a manner that the pressure is increased progressively and stepwise for a predetermined period of time. The molding tool is finally cooled to permit the removal of a newly-formed bicycle frame, which is light in weight, strong and tough.

Abstract: According to one example of embodiment of the invention a ceramic pre-moulding 81 of stable form is pressed from ceramic composition in powder form in a first isostatic pressing action, at least a part of its surface being formed in contact with rigid shaping surfaces 42. The pre-moulding 81 thus obtained is then--possibly after glazing-subjected to a higher pressure, in a further pressing operation on all sides and then fired in a ONCE-ONLY quick-firing method.

Abstract: A uniformly expandable mold is formed with a continuous surface defining a three-dimensional pattern for replicating an article. The relative pressure between the inside of the mold and the outside controls the area of the surface to change the size of the three-dimensional pattern without distorting the relative dimensional relationship of the component segments forming the pattern whereby material may be deposited on the mold surface with the mold expanded to a desired size. The pressure differential is increased to increase the size of the mold and stretch the layer already deposited thereon. A second, dissimilar layer is bonded to the first layer while it is streched When the article is removed from the mold, a state of relative expansive/compressive tension is created at the bond interface between the first and second layers which forces the material of one layer to enter voids in the other layer to seal defects.