Abstract: Disclosed is a method and apparatus for use in a fusion process for conduit. The method includes the steps of: removably positioning a first terminal edge of a first conduit portion with a first terminal edge of a second conduit portion; facing the terminal edges of the first conduit portion and the second conduit portion; aligning the terminal edges of the first conduit portion and the second conduit portion; melting at least a portion of the terminal edges of the first conduit portion and the second conduit portion; engaging the melted terminal edge of the first conduit portion with the melted terminal edge of the second conduit portion; maintaining pressure between the engaged terminal edges, thereby creating a fused joint area; and removing at least a portion of the resultant external bead extending around the fused joint area. A fusion apparatus for employing this method is also disclosed.

Abstract: A mold for forming plastic elements or for welding plastic elements to one another includes a thermocouple having its metallic elements welded to the mold to provide an accurate indication of the temperature of the mold. The metallic elements may be welded at a common location or at spaced apart locations. A circuit responsive to the temperature indication provided by the thermocouple controls the heating of the mold to maintain it at a predetermined temperature.

Abstract: A system for manufacturing interstitial radiation seed strand implants is provided. The system includes a seed dispenser, a member for handling an elongated half-shell member; and a controller in communication with the seed dispenser. The controller commands the seed dispenser to place the radioactive seed elements at desired locations in a first elongate half-shell member. The first half-shell member is mated with a second half-shell member to form a seed strand implant. The seed strand implant is axially stiff and longitudinally flexible, and constructed from bioabsorbable material.

Abstract: A method for molding the fiber aggregate comprising placing divided members of a mold obtained by dividing the mold having gas permeability into the plurality of members in a developed state, filling cavities of the divided members of the mold in the developed state with the fiber aggregate wherein binder fibers having a lower melting point than that of crimped synthetic staple fibers are dispersed and mixed in matrix fibers composed of the crimped synthetic staple fibers, respectively, uniting the divided members of the mold in the developed state, uniting each divided and filled fiber aggregate, heating the united fiber aggregate, melting or softening the binder fibers, fusing the melted or softened binder fibers to the matrix fibers at their crossing points, then cooling and solidifying the melted or softened binder fibers and providing a molded product and an apparatus therefor.

Abstract: Apparatus and method for the use of a remotely actuated localized pressure and heat apparatus for the consolidation and curing of fiber elements in, structures. The apparatus includes members for clamping the desired portion of the fiber elements to be joined, pressure members and/or heat members. The method is directed to the application and use of the apparatus.

Abstract: A six station rotary thermoforming machine includes a first oading station for first or upper panels, a second loading station for second or lower panels, two adjacent stations for heating the panels, a thermoforming station, an unloading station and a carousel for transferring thermoformable panels between such stations. The carousel includes a rotating circular frame which is driven by a centrally disposed drive assembly. The circular frame carries and supports six carrier assemblies having peripheral clamping members which receive panels of thermoformable material and rotates to sequentially move them from one station to the next. The two heating stations each include upper and lower radiant heaters. The thermoforming station includes a pair of opposed, vertically translatable platens which receive respective molds which engage and form the panels and may include a device for loading performs or inserts.

Abstract: An apparatus for heating a pin shaped thermoplastic material is provided including a quartz tube, a heat radiator and a securing mechanism. The quartz tube has tube ends and is helix shaped. The heat radiator is arranged in the quartz tube and includes an electrical resistance wire connected to a power supply. The securing mechanism is a heat resistant element connected to the quartz tube that secures the part to be heated relative to the quartz tube along an axis of the quartz tube and heats the plastic part. The quartz tube and/or the part to be heated are moveable. An apparatus is also provided for heating a number of pin shaped plastic parts simultaneously. In addition, a method for heating one or more pin shaped plastic parts is also provided.

Abstract: Apparatus for converting a flexible liner 2 including a layer 3 of composite material comprising thermoplastics material and reinforcing fibres, into a structural member within a duct 1, has a front portion 6 for insertion in the liner 2, a central portion 7 for heating one side of the layer 3 and a rear portion 20 which forces the heated layer 3 against the duct 1 for consolidation and cooling under pressure. The central portion 7 has heating means 8 producing hot gas which is forced under pressure through the layer 3 of composite material to heat the layer 3, and provides an air gap 14 on the opposite side of the layer 3 while heating takes place. This ensures uniform heating of the layer 3, to melt the thermoplastics material which then mixes intimately with the reinforcing fibres, and is consolidated and cooled to form the structural member.

Abstract: A twin sheet forming system and method is used to form a hollow article, such as an automotive fuel tank, from first and second sheets of thermoplastic material. The system includes first and second loading stations, first and second heating stations, and first and second thermoforming stations in an in-line arrangement. The in-line arrangement allows the sheets to be transferred independently between the stations and the separate thermoforming stations allows the sheets to be thermoformed independently. Each of the thermoforming stations includes an upper and lower platen generally in a side by side arrangement for supporting thermoforming tools and plug assists. After heating, the sheets are independently transferred to the thermoforming stations and formed using the thermoforming tools and plug assists. The thermoforming tool and thermoformed piece in one of the thermoforming stations is then transferred to the other station, and the thermoformed pieces are fused together.

Abstract: The apparatus for connecting objects by means of a plastically deformable connecting body comprises a shaping punch (4), a flow-restricting wall (5) closely surrounding the shaping punch and a gas supply lead (6) through which a gaseous medium can be introduced into the gap between the shaping punch (4) and the flow-restricting means (5). The shaping punch (4) has a heating cartridge (8) by means of which the lower end of the shaping punch can be heated. Provided on the outside of this shaping punch are heat-transfer ribs (9) which are used to heat up the supplied, gaseous medium which emerges at the lower end of the flow-restricting means in order to produce a flow around a plastically deformable connecting body (3), so that the latter is uniformly heated for the deforming process. The connecting body (3) is also integrally formed on a part (2) and reaches through a hole in a second part (1) which is to be connected to the first part.

Abstract: A thermoforming apparatus for forming sheets of sheet plastic onto a substrate in which a retractable substrate heater is able to be positioned over a substrate loaded into the press and energized while a plastic sheet is being heated in an oven included in the thermoformer apparatus. The plastic sheets are cut from a strip pulled from a roll of sheet material, the roll supported for side to side movement and driven by a servomotor responsive to error signals generated by a strip edge sensor to compensate for wandering of a strip edge to thereby insure accurate location of plastic sheets cut from the unwound strip.

Abstract: An apparatus and method for bonding polymeric materials is disclosed. The apparatus and method both utilize ferromagnetic materials in association with the polymeric materials to be bonded together. The polymeric materials, and the ferromagnetic material, are placed within a magnetic field, which causes hysterisis losses in the ferromagnetic field, and thus elevation in the temperature of both the ferromagnetic material and the polymeric materials to the point where the polymeric materials melt and fuse together. The ferromagnetic materials only rise in temperature to their Curie temperatures, at which point the hysterisis losses cease, and the polymeric material stops being heated. Removing the electromagnetic field allows for cooling and fusing.

Abstract: An apparatus and a method to deform a plastic rivet is described herein. The apparatus comprises a generally tubular outer wall configured and sized to enclose the rivet to be deformed and a piston slidably mounted in the generally tubular outer wall for longitudinal movements between a rest position and a pressure applying position. The deformation of the plastic rivet occurs when said piston moves towards the pressure applying position.

Abstract: An apparatus for heat staking utilizes an infrared lamp to direct radiant energy onto a plastic part to heat and so soften it prior to the staking punch impacting the part. The apparatus comprises an energy directing means for concentrating the infrared energy onto the part, and a moveable carriage for moving the punch toward and away from the part. One embodiment of the energy concentrating means is a reflector, wherein the reflector includes a central aperture for admission of the part, and wherein the reflector comprises different curved sections for concentrating the energy over the surface of the part. In an alternate embodiment, the energy directing means comprises fiber optic cables for directing the infrared energy to the surface of the part.

Abstract: A film and heated plastic blank are sized to fit over a mold cavity and a combination of said film and blank formed. The combination is positioned over the mold cavity and formed in said mold cavity into the shape of said mold cavity.

Abstract: The present invention is a machine and process for manufacturing an article such as a body board having a pre-shaped core member having a top surface and a bottom surface, a top skin having a top and bottom surfaces, a perimeter portion, and a perimeter edge, and a bottom skin having a perimeter portion. In one embodiment, the machine of the present invention comprises a first mold halve having a lower surface and a second mold halve having a lower surface and a plurality of side walls extending upward from the bottom surface. The second mold further comprising at least one seam member engaged with each side surface. The machine further comprises a control unit for opening and closing the first and second mold halves.

Abstract: A multilayer ornament, that is formed of a back of foam and a sheet of ornament, is brought on a support portion of the part, that it surrounds in the edge region. In a first step, the ornament is brought onto the part and is maintained in at least one edge region. Then, in a second step, the thickness of the foam is reduced by heating in the edge zone and/or stretching. And, in a third step, the ornament assembly or the projecting sheet of ornament is fixed onto at least one edge of the part.

Abstract: An improved, economical, high speed method and apparatus for attaching a fibrous material to a plastic substrate involves positioning a fibrous material over a surface of a plastic substrate, directing a stream of heated air through the fibrous material and at the surface of the plastic substrate to melt the surface of the plastic substrate, compressing the fibrous material against the melted surface of the plastic substrate, and allowing the melted surface of the plastic substrate to cool and resolidify, whereby fibers of the fibrous material become embedded in the resolidified plastic.

Abstract: Processes are disclosed for producing plastic containers from thermoplastic sheets where the thermoplastic sheets are processed in parallel to form a low permeation plastic container. A plurality of thermoplastic sheets are progressively heated to a first temperature in a pre-conditioning stage. A group of the thermoplastic sheets are selected from the plurality of thermoplastic sheets and rapidly heated to a second temperature in a final heat stage. The group of thermoplastic sheets are then processed in a forming stage to form the low permeation plastic container.

Abstract: An apparatus for heat staking utilizes an infrared lamp to direct radiant energy onto a plastic part to heat and so soften it prior to the staking punch impacting the part. The apparatus comprises an energy directing means for concentrating the infrared energy onto the part, and a moveable carriage for moving the punch toward and away from the part. One embodiment of the energy concentrating means is a reflector, wherein the reflector includes a central aperture for admission of the part, and wherein the reflector comprises different curved sections for concentrating the energy over the surface of the part. In an alternate embodiment, the energy directing means comprises fiber optic cables for directing the infrared energy to the surface of the part.

Abstract: A head for use in a heat staking machine utilizes an infrared heat lamp and reflectors to direct radiant energy onto a plastic stud to heat and so soften it prior to the staking punch impacting the stud. The lamp is disposed within a parabolic primary reflector which directs the lamp's output toward a secondary reflector. The secondary reflector has is concave and has a central aperture at its vertex through which the stud projects such that all of the radiant energy emitted by the lamp is focussed radially inward onto the stud. The punch is slidably mounted to the primary reflector for reciprocal movement along the axes of the reflectors, and is extended to impact the stud.

Abstract: A machine for heat staking utilizes an infrared heat lamp to direct radiant energy onto a plastic stud to heat and soften the plastic material prior to the staking punch impacting the stud. In a first embodiment of the invention, the lamp is mounted directly above and in coaxial alignment with the staking punch such that the lamp points downward toward the plastic stud. An annular reflector is positioned in a radially surrounding relationship to the stud such that all of the radiant energy emitted by the lamp strikes the reflector and is redirected radially inward onto the stud. In an alternate embodiment of the invention, an infrared lamp is mounted on a non-moving portion of the staking press machinery and one or more fiber-optic cables extend from the lamp to the vicinity of the stud. The fiber-optic cables gather substantially all of the radiant energy produced by the lamp and direct it onto the stud.

Abstract: Multiple legs elevate a central ring bearing, to which a ring-shaped rotatable plastic sheet support carousel is mounted. The carousel is fitted with a ring gear which engages with a drive system to position the carousel and the thermoplastic sheets supported from it. A multi-post vertical press is positioned with two posts extending upwardly interior to the ring bearing, and two posts extending upwardly exterior to the ring bearing. The ring bearing thus extends through the press, allowing the carousel to supply and remove plastic sheets to and from the press. An upper platen and a lower platen are mounted for vertical displacement to the posts, thereby ensuring a high degree of parallelism between the molds mounted to the platens, and accurate twin-sheet thermoforming.

Abstract: An improved pipe belling process is shown which features a mandrel having spring loaded detents at one circumferential position on an outer working surface. A gasket is installed on the outer working surface in abutment with the exposed detents. The heated socket end of a thermoplastic pipe is forced over the mandrel exterior and over the gasket with the detents in an extended position. This action causes the heated socket end of the pipe to flow over the gasket and form a retention groove for retaining the gasket before again contacting the working surface of the mandrel. The heated end of the pipe is cooled and retracted from the working surface of the mandrel. The retraction step serves to force the spring loaded detents to the retracted position to allow travel of the thermoplastic pipe over the working surface of the mandrel with the gasket being retained within the formed groove.

Abstract: Multiple legs elevate a central ring bearing, to which a ring-shaped rotatable plastic sheet support carousel is mounted. The carousel is fitted with a ring gear which engages with a drive system to position the carousel and the thermoplastic sheets supported from it. A multi-post vertical press is positioned with two posts extending upwardly interior to the ring bearing, and two posts extending upwardly exterior to the ring bearing. The ring bearing thus extends through the press, allowing the carousel to supply and remove plastic sheets to and from the press. An upper platen and a lower platen are mounted for vertical displacement to the posts, thereby ensuring a high degree of parallelism between the molds mounted to the platens, and accurate twin-sheet thermoforming.

Abstract: An apparatus is provided for manufacturing a lampshade from a heat-deformable sheet material. The apparatus includes a first supporting assembly for supporting a hollow body formed from the heat-deformable sheet material, the hollow body having upper and lower peripheral edges. A second supporting assembly is provided for releasably supporting a forming and stiffening ring in peripheral engagement with an interior surface of the hollow body adjacent a peripheral edge of the hollow body so that a marginal edge portion of the hollow body projects beyond the forming and stiffening ring. The second supporting assembly is located adjacent the first supporting assembly and includes a retractable supporting assembly for engaging an underside and an upper side of the forming and stiffening ring.

Abstract: The present invention relates generally to a new apparatus and method for forming cavities without using an insert. More particularly, the invention encompasses apparatus and method for fabricating cavities in MLC (multi-layer ceramic) without using inserts.

Abstract: The present invention relates generally to a new apparatus for forming cavities without using an insert. More particularly, the invention encompasses apparatus for fabricating cavities in MLC (multi-layer ceramic) without using inserts.

Abstract: A method for joining at least two plastic elements in a liquid- and/or gastight manner, whereby an edge of a first plastic element is at least partially placed in an opening of a second plastic element, the edge of the first plastic element being folded over an edge of the opening of the second plastic element under plastic deformation, using a pressure device. The edge of the first plastic element is pressed against a curved butting face of a pressure body placed in the second plastic element at the opening thereof and the edge of the first plastic element along the butting face is pushed radially outwardly and over the edge of the opening of the second plastic element. The edges of both plastic elements are pressed together by exerting pressure on both sides of the edges. Alternatively, use is made of a sealing ring at least partially between the edges.

Abstract: At a first station 202, flexible material 204 is deformed into a predetermined configuration defined by a mould recess 210. This configuration corresponds to the internal configuration of one of two housing parts 136, 138, situated at a second station 206. The deformed region of the flexible material 204 is advanced to the second station and secured between the housing parts 136, 138, to form a flexible partition within the container so formed.

Abstract: A tool for deep-drawing and sealing open plastics shells (3, 3') has a shell-like metal body (2, 2') which includes a flat edge (11, 11') at the open side. A heat insulating attachment is secured to the edge of the metal body so that the outer seam of a first plastic shell can be joined by sealing, to the outer seam of a second plastic shell oppositely disposed to it without supplying additional heat.

Abstract: In a method for connecting pipe pieces of corrugated pipes to form a pipe, which is to be used in particular as a protection pipe for communication cables or light wave guides, external pipe segments are formed by appropriate cutting in the vicinity of the external pipe portions, which external pipe segments are inserted into recesses of welding sleeves. These welding sleeves comprise an outer ring and an inner ring, the inner ring not projecting radially beyond the inner pipe portions into the pipe. At least one of the rings is welded with the external pipe segments.

Abstract: A method and apparatus for manufacturing a composite article. The method comprises the step of providing an autoclave having a platen, applying a composite article onto a work tool, and positioning the work tool on the platen. The platen is heated to transfer heat from the platen to the work tool and from the work tool to the composite article to cure that article; and a heat conductive, flexible mat is positioned between the platen and the work tool to maintain a desired thermal conductivity between the platen and the work tool during the heating step.

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 hot air cold form pin welding device for use in assembly of work pieces using thermoformable and pressure deformable synthetic resin studs. A hot air heater is positioned in a support structure that isolates heat transfer along with multiple power and air cycling to reduce heat build-up. The cold forming pin assembly with internal heat dissipation and airflow structure forms and presses a replasticized pin significantly reducing the cold pin press cycle time.

Abstract: A method for making an optical fiber bundle which, in one aspect, includes bending each of a plurality of optical fibers to form a bend therein and then suspending the fibers over a suspension member; holding the fibers taut under tension; applying potting material to the fiber bends and curing it; and removing the fibers from the suspension member.

Abstract: An improved apparatus particularly well adapted for installing a liner within a service pipe having an access end and a terminal end, the liner having a part which is everted and then inflated by the insertion of a fluid thereinto, the fluid being thus inserted by way of a conduit movable into the everted liner part by sliding through the eversion apparatus, the apparatus being further provided with appropriately located winches for controlling the movement of that part into and out of the service pipe.

Abstract: A device for producing pellets from film. A cradle is rotatably mounted about a longitudinal axis of rotation to a main frame. All axle arranged perpendicular to tim longitudinal axis holds a roll of film within the cradle. A second roll of film is mounted outside of the cradle, is held by a second axle arranged perpendicular to the longitudinal axis of the cradle, and is fed into the cradle to a position adjacent and parallel to film unwound from the first roll. A plurality of drive rollers pull the film from the rolls while the rolls are rotated about the longitudinal axes twisting the film into a strand. An oven located between the rolls and drive rollers heats the strand to permanently set the twist therein. A pelletizer located aft of the drive rollers cuts the strand into individual pellets. In a modified version, the second roll is split into multiple sheets prior to entering the cradle by one or more film splitters.

Abstract: According to the invention, calibrated rings are obtained by superficially vulcanizing extruded or profiled extrudate at the exit of an extrusion head (T), then by cutting this vulcanized extrudate into portions by means of a conical cutting device (C), subsequently by butting the two ends, in the respective form of a conical tip and a funnel, of each portion (t) together under hot conditions and under a controlled pressure, in order to obtain a ring blank which is then engaged between the half-cavities of a mold (Mo), where it undergoes shaping and vulcanization by the heating of the latter and thereafter deburring as a result of a shearing action produced by a push device (D) causing the half-cavities to slide in the closed position in the frame of the mold, before causing the opening of the latter by means of a device (G) and the release of the calibrated and superficially clean ring obtained.

Abstract: Apparatus for inserting a generally U-shaped liner into a pipe and reforming the U-shaped liner into a generally cylindrical cross-section to line the pipe includes winches for pulling the U-shaped liner through the pipe, pigs for cleaning the pipe, manifolds to connection at opposite ends of the pipe and wedge-shaped expansion members for initially mechanically reforming the ends of the liner projecting from the pipe. The wedge-shaped members include bores for communicating fluid at elevated temperature and pressure within the liner for setting the liner in generally cylindrical configuration against the pipe wall. A flaring tool is used to flare the opposite ends of the liner.

Abstract: Apparatus for pultruding thermoplastic, resin-impregnated, fibrous substructures heats the substructures to a temperature just below the melting temperature of the resin. The heated substructures are then simultaneously pulled through a passage to conform them to a desired cross section. At least a portion of the perimeter of this passage is formed by a wave guide. The wave guide is vibrated at ultrasonic frequency in a predetermined direction so as to direct the ultrasonic vibration into the substructures within the passage. The application of the ultrasonic vibration stimulates the flow of the resin in the heated substructures. Pressure is applied to the flowing substructures within the passage to consolidate them into an integral structure conforming to the chosen profile. The ultrasonic vibration at low power input does result in some heat transfer to the profile, but the flow rates of the resin exemplify an increase in flow far greater than expected in relation to the temperature increase.

Abstract: Mechanically robust star couplers of polymer optical waveguides having low insertion losses and small fluctuations between the individual output fibers are obtained if polymer optical waveguides are arranged in parallel in the middle region of an apparatus and fused with one another under pressure and with the supply of heat. The optical cladding of the polymer optical waveguides has been previously removed. The method is easy and cost-effective. The apparatus is composed of a lower part with a channel recessed therein and an upper part with a male die located therein, which male die corresponds in its shape to the shape of the channel.

Abstract: One method of forming a workpiece made of thermoformable material includes the steps of: (a) supporting a raw workpiece on a suspension tray; (b) moving a pair of relatively hot forming dies into position above the workpiece; (c) closing the hot forming dies against the workpiece to heat the workpiece and to form and shape the workpiece into the desired configuration; (d) opening the hot forming dies and removing the hot forming dies away from the workpiece; (e) moving a pair of relatively cold forming dies into position above and below the workpiece; (f) closing the cold forming dies against the workpiece to cool the workpiece while maintaining the workpiece in the desired configuration; and, (g) opening the cold forming dies and removing the finished workpiece form the suspension tray. Other methods are also disclosed.

Abstract: The process for making a plastic container by blow molding of a tubular parison made of a thermoplastic material, includes guiding a tube into a divided open blow mold, closing the blow mold and feeding pressurized air in the tubular parison squeezed off in the blow mold. However in the open blow mold which has a suitable receptacle at least one single-piece hoop ring made of thermoplastic material which could be made with usable tolerances by injection molding is mounted on the section and bonded with the tubular parison. An unsorted container ring which has an outer collar is used in the process and is fed to a preheat station in which the container ring is made stress-free and simultaneously is oriented in a plane.

Abstract: An apparatus for welding tubular components of thermoplastic material. The apparatus includes a heating device for heating the ends of the tubular components to be welded together until the melting range of the thermoplastic material is reached. Two outer support rings which are slid toward each other after the thermoplastic material has melted and an expandable inner support member ensure that welding pressure is built up, so that a welded connection can be obtained which is strong and free of welding beads.

Abstract: A gaseous medium, preferably compressed air or nitrogen, is introduced into the interior of the tubular components to be welded together from one end and is discharged at the other end through a throttled outlet opening. As a result, an excess pressure is built up in the interior of the tubular components and the inner wall of the components is cooled. When heating the abutting ends of the tubular components by means of a heating device, the ends are not melted entirely through to the inner walls, so that the formation of an inner welding bead is avoided and the internal pressure creates a welding pressure.

Abstract: An installation is characterized in that a molding unit is fixed in unremovable fashion on a supporting unit equipped with means for controlling the vertical movements of banderole shaping members; the carriage of the banderole introduction and transverse cutting unit comprises two partial carriages placed one behind the other; the first partial carriage is fastened removably onto the supporting unit; the second partial carriage is coupled to one lateral end of the first partial carriage; and the supporting unit is removably mounted on the press table and can move thereon parallel to the direction of motion of the partial carriages.

Abstract: In order to achieve defined fiber orientation angles in the fiber-reinforced plastic material of a hollow shaft, consisting of such material, the hollow shaft having regions of different diameters, a braided fiber tube constituting the starting material is pulled over a core, is impregnated with settable plastic, and is hardened.

Abstract: A method for contact fusion bonding of compressible, low density thermoplastic parts is disclosed, which comprises essentially: (a) fluidizing only a surface film on opposed mateable margins of the thermoplastic parts by precompressing the margins against a transversely stationary heated platen located therebetween and, prior to fluidization, continuing such contact to promote such fluidization by thermal conductivity and make heat-settable a limited, predetermined, nonmelted subsurface layer of said mateable margins; and (b) within a time period during which said surface films remain fluid, withdraw said platen from between said opposed margins with minimal separation while bringing the mateable margins together with sufficient force to merge said fluid films and compress said subsurface layers a predetermined moulded dimension.

Abstract: A shear head in which an extruded vulcanizable composition meets preheated reinforcing strands has a compartment adjacent a mouth of the head which is evacuated to reduce the danger of gases affecting adhesion of the strands to the composition.