Abstract: The object of this invention is to provide a hybrid composite journal bearing which is constructed so that a composite liner is positioned on an inner surface of a metal housing having a circular cross-section, thus preventing a journal from being broken or damaged or seized to the bearing, due to friction between the metal or composite journal and the journal bearing. The hybrid composite journal bearing (210) includes a metal housing (211) which is secured on an outer surface thereof to a bearing system and has a circular cross-section. A composite liner (212) is laminated to an inner surface of the metal housing (211) with a uniform thickness so as to minimize friction between the journal bearing and a journal.

Abstract: A stitch-free football structure includes a ball bladder formed by providing a yarn layer on an outer surface of an inflatable bladder and a glue layer on an outer side of the yarn layer, and a prolate-spheroidal structure formed by adjoining curved panels having configuration corresponding to the ball bladder and glued to an outer side of the glue layer; and a lacing-shaped patch glued to a seam between two adjoining curved panels to meet a required football configuration. In a method of manufacturing the stitch-free football structure, a plurality of curved panels is prepared in advance by hot press molding, and the curved panels are joined and attached to a ball bladder by gluing. Thus, the procedures for manufacturing a football are simplified, the bad yield in manufacturing is reduced, and the produced football is more durable for use, has more precise dimensions, and beautiful and even exterior appearance.

Abstract: A hollow upper deck panel for a plastic pallet has a solid top surface and is produced by forming a tubular hot plastic parison and directing the parison between blow mold sections to form upper and lower sheets for the deck panel. The lower sheet is blow molded by pressured air within the parison into a mold section to form spaced inverted U-shaped open ribs projecting upwardly and with top portions fused to the upper sheet. The upper sheet is blow molded by the air around retractable blades to form spaced closed double wall ribs projecting downwardly between the open ribs and have bottom portions fused to the lower sheet. The closed double wall ribs extend transversely to the open ribs and have end portions fused to the open ribs. The support structure for the upper deck panel defines spaces for receiving parallel spaced forks of a forklift truck.

Abstract: An object of the present invention is to provide a core member for a sandwich panel and a method of forming the core member for the sandwich panel which are capable of attaining a desired profile, a desired pattern on its surface, and a desired inner structure in accordance with an application of the sandwich panel. According to an aspect of the invention, there is provided a thermoplastic resin core member interposed between two resin skin sheets comprising a closed hollow portion located to be inside of a desired position in accordance with an application of the sandwiched panel, and it is formed by clamping parison of a molten thermoplastic resin positioned to be between two split molds so as to exhibit a desired profile and/or a surface shape, two surfaces against each of which the molten parison is pressed to form an adhesive surface on which the corresponding resin skin sheet is formed.

Abstract: An extrudable polyvinyl chloride composition comprising from 80 to 99.9 percent by weight polyvinyl chloride for use in extruding a first part and a second part, wherein a fusion joint between the first extruded part and the second extruded part is formed by: A) composition at least a portion of a first terminal edge of the first extruded part and a first terminal edge of the second extruded part; B) engaging the melted terminal edges; and C) maintaining pressure between the engaged terminal edges to create a fused joint having a strength that is at least 50% of the tensile strength of the extruded part as measured by ASTM D638-2a. The extruded parts can be pipe sections.

Abstract: There is provided a printing device 12 that performs printing on each of first and second labels L1, L2 on the way of feeding out a raw strip sheet M, which is temporarily stuck with a first label L1 and a second label L2 having a smaller plane area than that of the first label on a release liner S, a peel plate 27 that peels off the first and second labels L1, L2 from the release liner S, first and second label suction plates 30, 31 that hold the respective peeled labels L1, L2, and a laminating device 17 that laminates the first and second labels L1, L2 with the adhesive layer of the second label L2 facing the adhesive layer of the first label L1. The adhesive layer of the first label L1 laminated with the second label L2 is exposed in a closed loop manner in an outer peripheral area all around the second label L2.

Abstract: An example method of sealing a laminate assembly includes preloading a laminate assembly having a plurality of laminations, pressurizing the laminate assembly, and pressurizing an enclosed volume disposed adjacent an end portion of the laminate assembly to hold the laminations in sealed positions.

Abstract: A sports ball includes an inflatable bladder, and a ball carcass. The ball pocket is constructed to have a true roundness shape, having an interior cavity receiving the inflatable bladder therein, wherein when the inflatable bladder is inflated, the ball pocket retains a true roundness shape of the inflatable bladder. The ball carcass includes a ball cushion and a plurality of carcass panels. Each of the carcass panels has a peripheral edge and a flat bottom surface defined within the peripheral edge, wherein the bottom surface of each of the carcass panels is entirely affixed to the ball cushion at a position that the peripheral edge of each of the carcass panels is fittingly aligned with the peripheral edges of the adjacent carcass panels to form a roundness carcass of the sportsball in a stitch-less manner.

Abstract: A multi-ply, expanded content wrap label includes a base ply and an upper ply thereon with adhesive applied to the underside of a trailing end of the base ply to form a splice between the base ply and the upper side of the upper ply when the label is applied to a container.

Abstract: An extrudable polyvinyl chloride composition comprising from 80 to 99.9 percent by weight polyvinyl chloride for use in extruding a first part and a second part, wherein a fusion joint between the first extruded part and the second extruded part is formed by: A) composition at least a portion of a first terminal edge of the first extruded part and a first terminal edge of the second extruded part; B) engaging the melted terminal edges; and C) maintaining pressure between the engaged terminal edges to create a fused joint having a strength that is at least 50% of the tensile strength of the extruded part as measured by ASTM D638-2a. The extruded parts can be pipe sections.

Abstract: An inner mold having, on the outer surface thereof, corrugations matching the shape of the bellows, and an outer mold having, on the inner surface thereof, corrugations matching the shape of the bellows, are used. An airbag that is previously and at least partially formed into a bellows shape is placed on an outer side of the inner mold so as to cover at least a corrugated part with the airbag. A cylindrical preform comprising unvulcanized rubber and a reinforcement material is placed on the outer side of the airbag. An outer mold is placed on the outer side of the preform. A pressurized fluid is supplied between the inner mold and the airbag so as to inflate the airbag. The preform is vulcanized under heating while being pressed against an inner surface of the outer mold, whereby a reinforced rubber hose is manufactured.

Abstract: The present invention provides a method for the production of a tubular structural component. A tubular moulding tool having an inner mould surface which is shaped corresponding to an outer surface of the structural component is provided. A support surface of an expandable support which is formed such that in an unexpanded state, it fills the moulding tool, leaving an expansion spacing of the support surface to the mould surface, is covered with a tubular fibre-woven fabric. After the support has been arranged in the moulding tool, the fibre-woven fabric is pressed against the mould surface by expanding the support and is infiltrated by a curable matrix. From another point of view, a device is provided for the production of a tubular structural component.

Abstract: Method for manufacturing a cuff on a plastic tube comprising an inner tube and an outer sheath covering said inner tube. The outer sheath comprises at least a portion to be molded for producing a cuff. The method comprises a covering step including an injection operation in which air is intermittently or continuously injected between the inner tube and sheath.

Abstract: An annular convex portion is formed along an outer periphery of a back face of a wafer so as to surround a ground area in the back face. The annular convex portion is suction held by a holding table while being brought into close contact with the holding table, and fluid is supplied into a space defined between the back face of the wafer and the holding table. In this state, a separating adhesive tape is supplied toward a surface of a protective tape, and then a joining roller moves from a first end to a second end of the wafer while pressing the adhesive tape against the wafer. Then, a guide member moves from the first end to the second end of the wafer to guide the adhesive tape joined to the protective tape in a reverse direction.

Abstract: The invention relates to a method for producing an integral, reinforced fibre composite component comprising at least one hollow reinforcing component made of fibre composite material and shell component, comprising the following method steps: providing a mould core formed of a hose having a target cross-section deviating from a round cross-section and is adapted to an inner cross-section of the hollow reinforcing component to be produced, at least in portions, or substantially corresponds with said inner cross-section, at least in portions; introducing the mould core into a cavity in the at least one hollow reinforcing component; fixing the mould core in the at least one hollow reinforcing component using a fixing agent; applying the at least one hollow reinforcing component with the mould core fixed therein to the shell component; and subjecting the mould core to a pressurised medium and applying heat and/or pressure to this arrangement in order to produce the integral, reinforced fibre composite component

Abstract: A wind turbine blade includes an upper shell with a first portion molded to a second portion by a seamless connection extending along at least a majority of the width of the upper shell. The wind turbine blade also includes a lower shell with a third portion molded to a fourth portion by a seamless connection extending along at least a majority of the width of the lower shell. The first, second, third and fourth portions are made of a fiber reinforced resin construction. A first insert is enveloped within the upper shell between the first portion and the second portion, the enveloped first insert defining a first spar portion. A second insert is enveloped within the lower shell between the third portion and the fourth portion, the enveloped second insert defining a second spar portion. The inserts defining a density lower than the density of the fiber reinforced resin material. The upper shell is bonded to the lower shell adjacent the right and left sides thereof.

Abstract: A method for sterile connection of tubing includes welding the tubing sections together using an efficient laser. The ends of the tubing sections are brought together prior to the initiation of welding, facilitating isolation of interior passage of the tubing sections. The method can be carried out by an apparatus which is relatively inexpensive and compact.

Abstract: Embodiments of the present invention comprise a composite rim for used in spoked wheels, such as bicycle wheels, having molded-in spoke holes along with a method of fabricating the composite rim. Advantageously, the bearing and loading strength of the rim is improved over prior art composite rims wherein the spoke holes are drilled therein after fabrication of the rim hoop.

Abstract: Process for manufacturing gloves (2) and the like, which comprises the following operating steps:—inserting a lining (3) into a glove (2), wherein glue is arranged between the glove (2) and the lining (3);—inserting a plug (1) in the zone of the wrist of the glove (2) provided with the lining (3);—pumping a fluid into the lining (3) for pressing it from the inside against the inner surface of the glove (2). The present invention also relates to a device which carries out said process, as well as gloves or the like obtained with this process or device.

Abstract: A sportsball includes a ball carcass, an inflatable ball body received in a ball cavity of the ball carcass, and a stitchless seam arrangement which includes an elongated adhesive layer having a contour matching with a contour of an opening of the ball carcass, wherein after the ball body is disposed in the ball carcass, edge portions of the opening are adhered on an outer surface of the ball body via the adhesive layer, such that the opening is sealed to close the ball cavity for enclosing the ball body in the ball cavity of the ball carcass in a stitchless seam manner. Therefore, the manufacturing method of the sportsball excludes the traditional final assembling operation of hand stitching to reduce the time-consuming manufacturing procedure of the sportsball while being cost effective.

Abstract: A fluid-filled chamber may include an outer barrier formed from a polymer material and a foam tensile member located within the outer barrier. In manufacturing the fluid-filled chamber, a mold may be contoured to substantially equalize compressive forces between the outer barrier and various portions of the tensile member, thereby providing substantially uniform bonding between the outer barrier and the tensile member. Surfaces of the tensile member may also be contoured to substantially equalize compressive forces. In some configurations, the outer barrier and tensile member may be formed from thermoplastic polymer materials that form a direct bond between the outer barrier and surfaces of tensile member.

Abstract: A pipe lining composition and a method for installing the pipe lining composition into a pipeline requiring repair is provided. The lining composition is a layered lining composite formed of alternating plies of felt and carbon fiber strand reinforcing such that layers of carbon fiber reinforcing strands are trapped between layers of felt. Once the composite is laid up the composite is preferably stitched to provide stability and to maintain the layers relative to one another and then formed into a tube. In accordance with the method, the lining tube is then sequentially filled resins of increasing viscosity as it is drawn through rollers in a manner that fully wets out the carbon fiber before it is placed into the pipe to be lined.

Abstract: A fluid-filled chamber may include an outer barrier formed from a polymer material and a foam tensile member located within the outer barrier. In manufacturing the fluid-filled chamber, a mold may be contoured to substantially equalize compressive forces between the outer barrier and various portions of the tensile member, thereby providing substantially uniform bonding between the outer barrier and the tensile member. Surfaces of the tensile member may also be contoured to substantially equalize compressive forces. In some configurations, the outer barrier and tensile member may be formed from thermoplastic polymer materials that form a direct bond between the outer barrier and surfaces of tensile member.

Abstract: A method and apparatus for co-curing a multiple material golf club head is disclosed herein. The club head preferably is composed of a metal face component and an aft-body composed of a plurality of plies of pre-preg material.

Abstract: A tube shaped and fluid inflatable and electrically heatable in-situ pipe repair device comprising a first outer elastomeric tube layer and a resistive heating component comprised of electrically conductive fibers braided over an elastomeric core. The tube shaped device also contains an inner annulus. The device is fluid sealable and is connectible to a fluid supply and vacuum source. It is also connectible to an electrical power source. The device may also comprise two tube shaped layers configured to fit snuggly together with a resistive heating component held between the two layers. The resistive heating component may be a braided fiber-elastomeric core combination or a conductive fiber configured in a sinusoidal wave or similar pattern.

Abstract: A method of fabrication of a medical balloon, and a balloon device useful for various medical balloon procedures, such as gastrointestinal, vascular, reproductive system, urinary system and pulmonary applications. At least two layers of a thermoplastic film are sealed at their peripheral edges and heat sealed at one or more locations inside an area enclosed by the sealed edges at predetermined locations, in one implementation of the balloon device. Such configuration enables the balloon to articulate to a desired shape upon inflation, with the desired shape being selected to accommodate a specific medical application.

Abstract: A pressure container has an inner shell with a pair of fittings and a reinforcement layer formed around the inner shell, and is configured so that a reinforcement member is attachable to the pair of fittings in a process of forming the reinforcement layer and a functional component which performs a predetermined function is also attachable to the fittings. This can allow the reinforcement member to prevent expanding deformation of the pressure container in production of the pressure container, and can ensure effective use of openings after removal of the reinforcement member.

Abstract: A method for fabricating a grid-stiffened structure from fiber-reinforced composite materials. Ribs are formed on a smooth hard base tool. Expansion blocks are placed in the shallow cavities formed by the ribs and the base tool, and held in place by a synthetic elastomer-based adhesive while a skin is placed over the ribs, expansion blocks, and base tool. The assembly is then placed in a vacuum bag and autoclave cured. After cooling, the expansion blocks are removed and the formed structure is removed from the hard base tool. This abstract is provided to comply with the rules requiring an abstract, and is intended to allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: In a continuous molding apparatus equipped with a long core 10 having a curvature disposed on a plane, a release film supplied from a lower release film feeder 20 is sent onto the core 10, and prepreg sheets supplied from a prepreg sheet feeder 30 are laminated thereon and preformed. A release film supplied from a release film feeder 40 is disposed on top of the laminated body, before the body is sent into a hot press 50. A puller 60 moves the laminated body without loading tension thereto. The laminated body enters a postcure device 70 in which thermosetting of the material is completed.

Abstract: There is provided a pipe lining method wherein a lateral pipe lining material and a main pipe lining material are securely joined. After a lateral pipe has been lined, a start liner is applied to the main pipe and a main pipe lining material is then inserted. A heating wire for melting the start liner is mounted on a surface of a flange of the lateral pipe lining material during or after lining of the lateral pipe. While the main pipe is being lined, the heating wire is heated to melt the start liner existing between the flange of the lateral pipe lining material and the main pipe lining material. When the resin in the main pipe lining material is cured, the main pipe lining material and flange of the lateral pipe lining material are integrated. This allows the lateral pipe lining material and main pipe lining material to be reliably joined.

Abstract: An electronic device includes an electronic element having a detecting part on one surface thereof, a base member, bumps, and an adhesive film. The base member is arranged to face the one surface of the electric element. The bumps are arranged between the electric element and the base member for electrically coupling the electric element and the base member. The adhesive film is attached to the one surface of the electronic element and has an electronic insulating property. In addition, the adhesive film has a hollow part at a portion corresponding to the detecting part in a manner separated from the detecting part. Furthermore, a first pressure in the hollow part is higher than a second pressure outside the hollow part.

Abstract: A method for producing a lightweight end wall of a containers characterized by the following stages: manufacturing a large size lightweight thermoplastics tube by spirally winding and joining together a hollow profile of thermoplastics, cutting a piece from such a tube to form a pre-form of an end wall, heating the pre-form into a mouldable state, pressing the pre-form into a dome shaped piece between a male and a female mould-half, cooling the dome shaped piece while pressed between the mould-halves, maching-tooling the edges of the cooled piece to match the cross-sectional surface of the tube mantle, and joining the mantle and the end wall together by welding.

Abstract: A cast formed filter and a method for making the filter are provided. The cast formed filter includes a cast formed filter media having an inlet end, an outlet end, a plurality of inlet openings, a plurality of outlet openings, and a fluid path. The plurality of inlet openings extend from the inlet end into the cast formed filter media, wherein a first portion of the cast formed filter media is disposed between each of the plurality of inlet openings and the outlet end. The plurality of outlet openings extend from the outlet end into the cast formed filter media, wherein a second portion of the cast formed filter media is disposed between each of the plurality of outlet openings and the inlet end, the second portion comprising at least a portion of the first portion of cast formed filter media.

Abstract: A producing method of ball for ball game including a ball cover and a bladder is disclosed. The method includes steps of (a) inflating a bladder and providing a web layer by coating at least a thread on an outer surface of the bladder thereafter, (b) fabricating a plurality of panels in a predetermined shape, (c) sewing the plurality of panels edge to edge together excluding a portion thereof by a sewing machine to form a ball cover including an inlet opening, (d) inserting the bladder obtained at step (a) into the ball cover obtained at step (c) through the inlet opening, (e) sewing the inlet opening of the ball cover, and (j) inflating the ball for ball game to a predetermined pressure within a shaping mold.

Abstract: Self-adhesive labels are formed by repetitively cutting linerless web material which is fed from a roll into and through a rotary knife cutter. The labels are then transported to and applied to articles. To improve cutting of the web and labeling, the web and or labels are contoured, e.g., they are made concave, in a plane transverse to the direction of flow path. To contour the web or labels, alternative endless belt arrangements are used, wherein the center line of the adhesive side of the web is adhered to a belt surface. Preferably, a one-piece belt having spaced apart and movable lengthwise portions is used. Different transport velocities are used for web fed to the cutter and for labels taken-away from the cutter. Cutter motion, and thus label length, in forming either linerless and lined labels, is controlled according to how printed indicia bar marks on the web are severed into portions; alternatively, according to whether or not the cut falls between two spaced apart printed indicia.

Abstract: A device and method for the manufacture of medical devices, specifically, endovascular grafts, or sections thereof. Layers of fusible material are disposed upon a shape forming member and seams formed between the layers in a configuration that can produce inflatable channels in desired portions of the graft. After creation of the seams, the fusible material of the inflatable channels may be fixed while the channels are in an expanded state. A five axis robotic seam forming apparatus may be used to create the seams in the layers of fusible material.

Abstract: There is provided an apparatus and method for consolidation joining a thermoplastic preform to form a duct. The apparatus includes first and second longitudinally extending support structures. The first support structure at least partially defines a cavity for supporting the preform in a desired configuration of the duct. The second support structure extends in the cavity such that the preform can be supported between the first and second support structures. The second support structures can include an elastomeric device that is configured to adjust radially and urge the interface of the preform against the first support structure. A heater is configured to heat an interface of the preform to above a glass transition temperature. The resulting duct is has a longitudinal consolidation joint and defines a passage.

Abstract: A method of making a filament wound pressure vessel. A thermoplastic liner is filament wound with a commingled roving containing thermoplastic and reinforcing filaments. The wound tank is partially filled with a cooling liquid and the wound tank is heated to a temperature which is sufficient to vaporize a portion of the liquid to pressurize the liner at a preselected set pressure and sufficient to fuse the thermoplastic matrix, but insufficient to significantly soften the liner.

Abstract: A method for manufacturing a hub in particular for bicycles and the like, wherein a winding device comprising at least a first shaping device is provided, a predetermined quantity of fibers is deposited on said first shaping device, at least a first cross-linking agent is deposited on at least part of the fibers, said first shaping device is inserted into a second shaping device and said first shaping device with at least said fibers and at least said first cross-linking agent is expanded toward said second shaping device, wherein said shaping devices are matched relative to each other such that an expanded body comprising said fibers and said cross-linking agent has a substantially even thickness.

Abstract: A welded item is shown having an extruded weld bead with a high tensile strength relative to the layers from which it is formed. A valve with an insert is shown. A ball with an internal plenum is shown.

Abstract: A sports racquet comprises a handle and a frame coupled to the handle. The frame includes an inner portion and an outer portion located substantially opposite the inner portion. The inner portion of the frame include a plurality of undulations that extend towards and away from a ball-hitting surface, the undulations reducing the unintended bunching and wrinkling of material that intermittently forms in the frame during the manufacturing process. The undulations can be varied by location, undulation length, undulation height, and frequency and can be used in racquets made from a variety of materials and methods.

Abstract: An improved method of bonding involves using direct fluid pressure to press together the layers to be bonded. Advantageously one or more of the layers are sufficiently flexible to provide wide area contact under the fluid pressure. Fluid pressing can be accomplished by sealing an assembly of layers to be bonded and disposing the assembly in a pressurized chamber. It can also be accomplished by subjecting the assembly to jets of pressurized fluid. The result of this fluid pressing is reduction of voids and enhanced uniformity over an enlarged area.

Abstract: In manufacturing an air-bag (1) which is formed from two super-imposed layers of fabric (2) interconnected by a plurality of seams (3), a sealant material is applied to the interior of the air-bag. The sealant material is applied by introducing a mandrel (10) carrying a parison of the sealant material (11) into the air-bag, and injecting air into the mandrel.

Abstract: A method is disclosed for reinforcement of thin wall hollow thermoplastic storage vessels with one or more wraps of continuous fibers. This method requires thermal bonding between the reinforcement fibers and the outer surface of the thermoplastic storage vessel while the interior cavity of the storage vessel is being pressurized. The fiber wraps can also be oriented in spatial directions further resisting internal stress on the storage vessel walls when put in service.

Abstract: A fuel tank includes a vessel having a wall, the wall includes at least a first layer forming a hydrocarbon barrier, and a second layer that is more permeable to hydrocarbons than the first layer and is located on an outside of the first layer. The fuel tank also includes an insert defining a passage between an inside of the vessel and an outside thereof. The insert includes a first end overmolded by the wall and a second end opposite to the first end projecting outside the vessel. The wall has a portion extending inside the insert around an opening of the wall, the insert being configured to form at least one region of reduced thickness in the second layer along a diffusion path for hydrocarbons diffusing along the second layer from an edge of the wall adjacent to the opening towards the outside of the vessel.

Abstract: The invention relates to a film tube (10) based on cellulose which is produced by extruding an aqueous cellulose-N-methyl-morpholine-N-oxide (NMMO) solution through a ring nozzle (21) onto a lining (3). The film tube (10) is manufactured by means of a vertically descending spinning in a spinning vat (12) in which a spinning bath (11) is located. The film tube (10) which is submerged in the spinning bath (11) passes through an air gap (9) between the underside of a nozzle block (7) and the upper surface of the spinning bath (11) and, internally, is pressurized, supported and slightly stretched in a transversal manner by compressed air. The film tube (10) is filled with an inner bath solution (31) via a supply tube (18). An idle roller (13) is situated near the bottom of the spinning vat (12) in order to guide the film tube (10) around and, afterwards, out of the spinning vat (12) in an upward sloping manner. The film tube is laid flat along a contact section (27) of the idle roller (13).

Abstract: For the purpose of fastening cables to the inner wall of a non-accessible waste-water pipe, an internal liner has been developed, which is constructed from at least two layers, the first layer, which rests against the internal wall of the pipe when in the laid condition, having a profile or empty spaces for receiving cables, and a second layer, of envelope-like type, which carries the first layer.

Abstract: The apparatus and method for eliminating ground water infiltration while stabilizing the ground and repairing underground pipe/conduit and connections is taught in this art. The steps are to first inject, under pressure, expandable structural foam in the space adjacent and outside the pipe while blocking any infiltration of the foam into the interior of the pipe, conduit or connection. Concurrently or separately the inside diameter of the pipe is receiving a structural repair. The result is stabilized ground, elimination of ground water infiltration and repair of the host pipe conduit or connection.

Abstract: A drum for electrophotographic printing, which is easy to assemble and economical and which provides reliable electrophotographic charging and discharging. A drum core is provided and an exchangeable sleeve is applied to the outside of the drum core, which contains a layer made of an elastic, fiber-reinforced, and conductive plastic. Furthermore, the drum contains a layer made of an elastic, fiber-reinforced, conductive plastic. Due to the conductivity of the elastic, fiber-reinforced, conductive plastic, the electrostatic charges can flow to or from an object, whereby electrostatic illustration is made possible. The sleeve has high stability and high elasticity due to the above-mentioned characteristics and it can be charged or discharged as desired. The sleeve can be easily mounted on the drum core due to its light weight and high elasticity.

Abstract: Disclosed is a helmet or a safety cap for protecting the rider's head and a method of manufacturing the same, in which the main body of the helmet has a dual-structure so as to reduce work process when an outer surface of the helmet is painted, and weight thereof. The main body of the helmet has a dual-structure in that an outer surface thereof is formed of a thermoplastic for an aesthetic enhancement and an inner surface thereof is formed of FRP or a mixture of aramide fiber, polyethylene fiber, vinylon, carbon fiber. Thus-formed dual structure of the helmet body contributes to enhancement in impact resistance and convenience in painting, decreasing an overall weight of the helmet.