Abstract: A method for continuously manufacturing a complex acoustic multi-element panel for an acoustic attenuation structure, the method including supplying a thermoplastic resin film at the entry of a stamping system including at least one pair of complementary cylinders, a heating of the thermoplastic resin film upstream of the entry of the stamping system, and a passage of the thermoplastic resin film between the at least one pair of complementary cylinders, the pair of complementary cylinders including a male cylinder with teeth radially protruding from the cylinder and a female cylinder with cavities on its radial surface, the cavities of the female cylinder being of shapes complementary to the shapes of the teeth of the male cylinder and a separation of the stamped film at the exit of the stamping system using a separator disposed at the exit of the stamping system between the stamped film and the female cylinder.

Abstract: A molding method and a molding system for improving a molding speed of a resin molded member. In the method, firstly a thermoplastic resin composite material is filled in a metal mold (i.e., at time T0), and subsequently a mold-clamping process gets started. As the mold-clamping process progresses, a first decompression circuit starts to decompress an inside of a cavity when the cavity is closed by a sealing member provided on the metal mold. Then, as the mold-clamping process further progresses, the thermoplastic resin composite material thus filled in the metal mold contacts an upper mold of the metal mold (i.e., at time T2). After that, a second decompression circuit starts to decompress the inside of the cavity, thereby to complete the mold-clamping process (i.e., at time T3).

Abstract: A forming apparatus includes a base material jig provided on a base, adhesion means for making a sheet having an adhesion layer and covered to a base material retained on the base material jig adhere to the base material, and trimming means for performing trimming on the sheet with respect to the base material with the sheet adhered thereto, in a state in which the base material is not removed from the base material jig.

Abstract: The invention relates to a thermoforming device (10), in particular for cups (1) that can be filled with a foodstuff, having a mold (11) comprising an upper part (12) and a deep-drawing mold (13) arranged underneath the upper part (12) for molding at least one cup (1) in a heated sheet of film (2), wherein the deep-drawing mold (13) forms a side wall (4) and a bottom area (5) of the at least one cup (1).

Abstract: Mainly, local wall thinning is prevented. The invention relates to a vacuum forming method for fabricating a resin-molded article. The vacuum forming method includes pressing a thermoplastic resin sheet 201 softened by heating into a vacuum forming mold 202 using a core mold 203 to stretch and deform thermoplastic resin sheet 201 at the same time, and bringing the thermoplastic resin sheet 201 into intimate contact with the vacuum forming mold 202 by vacuum suction to shape the thermoplastic resin sheet 201. In the process of closing the vacuum forming mold 202 and the core mold 203, at least part of the thermoplastic resin sheet 201 is preshaped using air pressure in such a way that the at least part of the thermoplastic resin sheet 201 is locally stretched and deformed at the same time and thus brought into intimate contact with the core mold 203.

Abstract: A device for making a seamless, anatomically contoured, prosthetic device for supporting or maintaining the position of mammalian tissue, organ or structure or a replacement thereof, such as a breast implant, includes a support plate, an ironing plate or a clamping plate and a core plate, each of which is made from a thermally conductive material. The support plate and the ironing or clamping plates have openings formed through the thickness thereof. The core plate has a core extending outwardly from a lower surface thereof which is received through the openings in the ironing or clamping plate and the support plate.

Abstract: A method for producing appliance cabinets and the like, particularly a refrigerator cabinet having a double wall, whereby a polymeric sheet made plastic by thermal action is vacuum formed in a mold. The mold comprises a central male portion adapted to form the cavity of the cabinet and an annular female portion adapted to form the double wall of the cabinet, a plug assist device being used in order to drive the sheet in the female portion of the mold.

Abstract: The present invention provides an improved syntactic foam plug for plug assist thermoforming wherein such plug is composed of a thermoplastic material having a relatively high melting and/or glass transition temperature. Accordingly, the subject invention encompasses diminishing or removing the undesirable characteristics of thermoset syntactic plugs while increasing the ease by which these articles may be constructed for a given use, by forming such plugs from syntactic foams containing thermoplastics.

Abstract: A resin coated piston manufacturing apparatus for a shock absorber is provided with a means for pressing a piston raw material to a resin sheet until the resin sheet is locked to a resin sheet locking annular groove of the piston raw material in such a manner as to be capable of reciprocating on a center axis of a set mold. The apparatus having an aligning guide mateable with an inner diameter of the piston raw material set to a piston set hole of the set mold. The aligning guide presses the piston raw material to the resin sheet so as to lock the resin sheet to the resin sheet locking annular groove of the piston raw material, and can press the piston raw material to which the resin sheet is locked, to a heating and cooling cylinder apparatus.

Abstract: The present invention provides a bottomed cylindrical container, comprising a body wall, a bottom wall, and a ring-shaped foot downwardly extending from the bottom wall, said container being produced by thermo-molding a resin sheet, characterized in that said foot is formed by folding an inner wall by compressed fluid to be fusion-bonded with an outer wall, so as to form the foot comprising the inner wall and the outer wall. The present invention also provides a bottomed cylindrical container, comprising a body wall having a grounding edge at a lower end thereof, and a bottom wall, said container being produced by thermo-molding a resin sheet, characterized in that said bottom wall connects with an upper edge of an inner wall produced by folding back the body wall along the grounding edge and by fusion-bonding it to an inner periphery of the body wall. In addition, the present invention provides the methods for thermo-molding these containers and their apparatuses.

Abstract: A complex-shaped, three-dimensional fiber reinforced composite structure may be formed by using counteracting pressures applied to a structural lay-up of wetted fibers. The wetted fibers are arranged on pressurizable members and may be configured to include internal structural features, such as shear webs. A reinforcement stiffener may be located adjacent to at least one of the pressurizable members and the wetted fibers that form the internal structural feature. The reinforcement stiffener includes a modulus of elasticity that is substantially higher than a modulus of elasticity of the resin used to wet the fibers. In one embodiment, the reinforcement stiffener may be received in a pocket of one of the pressurizable members and may include a releasing agent that permits removal of the stiffener after the composite structure has been pressurized and cured.

Abstract: A manufacturing method for a sheet molded body having a desired three dimensional shape and an excellent quality of the design, which has no crease, by uniformly expanding a decorated sheet prior to molding, and closely contacting the decorate sheet to the surface of a male die. In the manufacturing method, the pressure at the front side of the decorated sheet is lowered relative to that at the back side. An arm means is then moved towards the decorated sheet from the back side of the decorated sheet so that the decorated sheet is inverted by increasing the pressure at the front side relative to that at the back side. The decorated sheet is then three dimensionally formed along the surface of the male die by, while pressing the male die from the back side and moving the arm means backwards, increasing the pressure at the front side.

Abstract: In a method for manufacturing a thermoplastic resin vessel, in which a cup-shaped vessel is thermally formed from a thermoplastic resin sheet by a plug, the method including the steps of: pre-forming a portion of the thermoplastic resin sheet corresponding to an orifice portion or a flange portion of the cup-shaped vessel; and clamping the pre-formed portion of the thermoplastic resin sheet to accomplish the forming. According to the manufacturing method, thickening of a vessel bottom part and warpage of the flange portion can be improved.

Abstract: A thermoforming method and objects prepared using the thermoforming method are described. Non-self-supporting, polymeric films are initially formed into a three-dimensional shaped film on a male mold and then transferred to a female mold while being supported by the male mold. The three-dimensional shaped film can be further thermoformed, reinforced, or a combination thereof on the female mold. The resulting object has a substantially uniform thickness across a major surface. The method can preserve the surface quality of the polymeric film used to prepare the three-dimensional objects.

Abstract: Disclosed herein is a top box assembly for use with gaming machines found in casinos, formed from vacuum processing, and the methods associated therewith. The vacuum-formed process for generating top box assemblies enables the efficient and economical production of visually attractive and unique top boxes including translucent spanning panels in conjunction with specially shaped front and rear panels.

Abstract: The installation for manufacturing objects such as receptacles by thermoforming pellets of thermoplastic material includes conveyor means for conveying the pellets through the various stations in the installation, said stations including a heating station and a thermoforming station. The conveyor means comprise conveyor elements (46) defining cells (48) which are open upwards and downwards, and each of which is suitable for containing one pellet (12) while the entire top and bottom faces of the pellet remain unobstructed, means for depositing the pellets in the cells, drive means for driving the conveyor elements through the heating station, and transfer means (20) for transferring the heated pellets to the thermoforming station. The heating station includes bottom heater means (52) that co-operate with a support for the pellets while said conveyor elements are being driven through the heating station.

Abstract: The present invention is directed to a method of preparing an article of manufacture. The method includes bringing at least a portion of a heated thermoplastic sheet into contact with at least a portion of the first surface of a support having a plurality of perforations. A vacuum is formed on the second surface of the support, and portions the heated thermoplastic sheet are drawn through the perforations of the support and to the second surface side of the support. Thermoplastic attachment heads are formed on the second surface side of the support, from the thermoplastic material of the sheet that is drawn through the perforations. The thermoplastic sheet and the support are fixedly attached one to the other by means of the edges of the perforations being embedded in the thermoplastic material of the sheet drawn therethrough, and the thermoplastic attachment heads. Also disclosed are articles of manufacture, such as interior and exterior automotive body panels and components.

Abstract: The present invention is directed to a method of preparing an article of manufacture. The method includes bringing at least a portion of a heated thermoplastic sheet into contact with at least a portion of the first surface of a support having a plurality of perforations. A vacuum is formed on the second surface of the support, and portions the heated thermoplastic sheet are drawn through the perforations of the support and to the second surface side of the support. Thermoplastic attachment heads are formed on the second surface side of the support, from the thermoplastic material of the sheet that is drawn through the perforations. The thermoplastic sheet and the support are fixedly attached one to the other by means of the edges of the perforations being embedded in the thermoplastic material of the sheet drawn therethrough, and the thermoplastic attachment heads. Also disclosed are articles of manufacture, such as interior and exterior automotive body panels and components.

Abstract: A method and apparatus for thermoforming deep drawn parts such as cups in which a vacuum is momentarily applied to a preheated sheet material when overlying a clamping plate prior to clamping and advance of the plug assists to delay contact with a lip molding feature projecting from each mold cavity. This avoids a molding defect due to premature cooling of a localized region of the sheet material when the sheet material comes into contact with the lip molding features.

Abstract: A plastic blow molded container having a central vertical axis constructed in accordance with the present invention includes a cylindrical upper rim, an oriented neck portion, a lower body portion, and a closed base portion. The upper rim of the container includes a top surface having a planar inner edge and an outer edge. The inner edge is generally flat and perpendicular to the vertical axis of the container and the outer edge may be curled or curved to provide additional rigidity. The oriented neck portion depends from the upper rim and includes a means to accept a closure, such as a set of integral threads. When viewed in vertical cross section, the outer vertical line formed by the outer axial points of said means to accept a closure is substantially parallel to the vertical axis of the container. The lower body portion is generally cylindrical over the majority of its vertical length. The closed base portion supports the container and depends from the lower body portion.

Abstract: On the-inside of heated molds hollow bodies are formed by vulcanization, the bodies are formed of elements from natural or synthetic rubber and/or treated elastomers, possibly associated with different materials such as leather, skin, cotton, metals, expanded rubbers and others, combined with each other. A pressurized fluid, such as hot or cold air, vapor or compatible gas, is injected between the hollow bodies being formed. During vulcanization, the components, airtight-coupled with each other along at least a contact and sealing common line, are pushed and kept in forming adhesion against the mold surfaces by the pressurized fluid.

Abstract: Compartmented food service articles with sharp angular junctions are thermoformed utilizing a plug-assisted thermoforming process. The plug is employed in connection with a thermoforming mold having a plurality of rib portions which project axially from a substantially planar mold surface of the thermoforming mold, and which rib portions define a plurality of angular junctions with the substantially planar mold surface. The plug includes a plurality of rib relief portions positioned and configured to fit about the rib portions of the mold in a forming operation at an axial clearance distance of about 0.125 inches or less from the angular junction of the rib portions of the mold with the substantially planar mold surface.

Abstract: Process for manufacturing cold formed shaped forms of packaging having at least one recess from a metal-plastic laminate. Examples of such shaped forms of packaging are the base parts of push-through packs or blister packs. The process is such that the laminate is held between a retaining tool and a die. The die exhibits at least one opening and a stamp is driven into the die opening causing the laminate to be shape-formed into a packaging, correspondingly exhibiting one or more recesses. The die and the retaining tool exhibit facing edge regions and the die, within the edge region, exhibits a shoulder region that surrounds the die opening or openings. The surface of the shoulder region lies 0.

Abstract: A method and apparatus for producing a thermoplastic container-shaped intermediate or article having biaxially oriented side walls and a bottom having an unoriented portion surrounded by a biaxially oriented transparent portion. In the method, a sheet of thermoplastic at its orientation temperature is secured over the mouth of a forming tube. A plunger having a circumscribing sharp edged lip and a plunger follower sandwich the thermoplastic sheet and the plunger and plunger follower are driven into the forming tube while preventing the circumscribed portion of the thermoplastic from becoming oriented. Thereafter the thermoplastic is blow formed to yield a container-shaped intermediate. The final container is formed by heat shrinking the intermediate onto a male form having a predetermined size, shape and texture. The apparatus includes the forming tube, plunger, plunger follower and pressurized air for performing the method.

Abstract: An apparatus for plug-assisted thermoforming of a cup or other hollow article has a concave well or cone region machined into its top with a series of small holes drilled near the deepest part of the well and connected to a port inside the plug which is connected to a specifically sized manifold system. The manifold has a source for positive (pneumatic) and negative (vacuum) pressure air. During the machine cycle, a vacuum is introduced into the plug, which draws the hot plastic sheet into the plug well to stretch it. The vacuum is replaced by compressed air to transfer the pre-stretched sheet into a mold. In a particularly preferred embodiment, the plug is shaped to provide stretching in both the central well and in peripheral regions concentric with the well. Controlled air pressure in the mold may be used to provide the concentric prestretching.

Abstract: The tip of the blow core on a stretch blow molding machine is slightly smaller in diameter than the neck of the preform into which it is inserted such that during both insertion and withdrawal there is no physical contact between the core and the preform. However, when the core tip is in place within the preform and the blow surge commences, a resilient sealing ring around the core tip expands into radial contacting engagement with the preform to seal off what would otherwise be an air escape route. When the air surge terminates, the ring contracts into a dove tail gland around the core tip so as to be substantially flush with the surface of the tip, permitting the core to be withdrawn without contacting the preform.

Abstract: A process for thermoforming a sheet, involving a static back-pressure which initially increases substantially continuously, then decreases substantially continuously, during the thermoforming operation. The back-pressure is preferably controlled by a pressure release valve.

Abstract: A method of and apparatus for moulding preformed material with a forming mould (1), tool, membrane or bag, in which as the material (A) is being moulded or shaped, a temperature controlled fluid is introduced at a sufficient pressure to act as a barrier between the material and the forming mould, tool, membrane or bag so that thickness of the article formed can be selectively controlled.

Abstract: Forming apparatus for forming hollow articles from a thermoplastic web wherein a mold block and a counter-mold block are respectively provided with the same number of forming chambers and cylindrical cavities. Each cylindrical cavity contains a forming punch having an inactive top portion and an active bottom portion, which active bottom portion is suitable for penetrating vertically into the corresponding forming chamber. The inactive portion of each forming punch extends over an axial height that is less than the maximum width of the punch. Each forming punch is surmounted by a guide piston which slides in sealed manner inside the corresponding cylindrical cavity of the counter-mold block. The annular space beneath the guide piston is suitable for communicating periodically with a source of compressed gas via at least one link duct.

Abstract: Cold-stretchable sheet material is isostatically formed at an operating temperature beneath the softening temperature of the sheet material by means of a fluid pressure medium at a pressure of more than 20 bars so as to produce a deep-drawn formed plastics piece. Forming may take place abruptly. The sheet to be formed may be provided with a coating such as an ink imprint. The resulting thin-walled deep-drawn piece may be backed and reinforced by injecting further plastics material.

Abstract: In the deep-drawn molding of a plastic container, a molten plastic sheet is positioned between a plug and a mold. The molten sheet is supported on an upper mold surface portion having heat insulating property and slipperiness, and while a positive pressure is created between the mold and the molten sheet, the molten sheet is molded by moving the plug and the mold relative to each other in a closing direction. By drawing the molten sheet into the mold while allowing it to slide over the above upper mold surface portion, the amount of the molten plastic sheet drawn into the mold is increased, and a container can be produced which has a uniform height direction and a uniform thickness distribution in the container height direction and possesses good appearance characteristics without the occurrence of a drag line in its side wall.

Abstract: A method of forming a twin sheet plastic pallet formed of an upper and a lower sheet and utilizing an upper male mold having downwardly extending leg protrusions and a lower female mold having complementary upwardly opening leg cavities. The method includes introducing the lower sheet between the spaced upper and lower molds, vacuum forming the lower sheet to the molding surfaces of the upper mold, vacuum forming the lower sheet to the molding surfaces of the lower mold, introducing the upper sheet between the spaced molds, vacuum forming the upper sheet to the molding surfaces of the upper mold, and bringing the upper and lower molds together with their leg portions in nested relation to fuse the upper and lower sheets together along their peripheries and at the interfaces their nested leg portions to form the final pallet.

Abstract: A method of making a split bearing sleeve having flanges at the opposed ends thereof for mounting a sprocket wheel on an axially extending shaft is disclosed herein. The method includes the steps of providing a mold having axially aligned recessed areas for the flanges and an intermediate area extending between the recessed areas for the flanges, placing a thin strip of polyethylene in the intermediate axially extending area such that the strip extends partially into the recessed flange areas, and pouring heated polyurethane into the mold to fill the recessed areas for the flanges and the intermediate axially extending area to encapsulate the thin strip in the recessed flange areas.

Abstract: A process and apparatus for manufacturing an embossed article of synthetic resin including heating a synthetic resin sheet to a softening temperature; pressing the heated synthetic resin sheet on an embossing die by a press die. The embossing die being made by an electro-chemical molding process and having an embossing surface with an embossing pattern thereon and a multitude of fine vacuum pores distributed uniformly over the entire embossing surface. Forcing the synthetic resin sheet against the embossing surface by applying suction through the fine vacuum pores to imprint the embossing pattern onto the synthetic resin sheet. The press die having an undercut shaping portion. Applying blowing pressure through the embossing dies and applying a vacuum through the undercut shaping portion. Thus, releasing the synthetic resin sheet from the embossing surface and forming an undercut in the synthetic resin sheet.

Abstract: A method of making a protective shield with an optically clear viewing portion by vacuum forming over a mandrel wherein the viewing portion of said protective shield is maintained out of contact with the mandrel to define the optically clear viewing portion.

Abstract: A method for the shaping of a sheet of preform material. A flat planar (heated) sheet of preform material is held tightly between two elastomeric sheets, the sheets and preform material forming a laminate assembly. The laminate assembly is then formed about a mold having the desired contours. The elastomeric sheets maintain the preform material parallel to the surface contours of the mold as the molding process proceeds. A fluid such as air is flowed between the mold surface and the laminate assembly during the forming process to prevent the elastomeric sheets from binding on the mold surface. Wrinkles are eliminated in the final shape of the preform material, and fiber distortion of tears or rips in the material are minimized due to the fluid lubrication between the mold surface and the laminate assembly.

Abstract: Method for the production of heat resistant polyethyleneterephthalate containers by means of thermoforming with a longitudinal and radial direction stretching of a sheet (1) of unstretched amorphous polymer in a die (2) kept at a temperature of about 175.degree.-180.degree. C. The container is consolidated and extracted by a counterdie (4), cooled and provided with suction means. The containers thus are stable at sterilization temperature in boiling water and in steam at 130.degree. C.

Abstract: Disclosed herein is an improved method for forming a double wall container by laminating a thermoplastic resin sheet for a container main body and a breathable thermoplastic resin sheet or film for an inner body with a low-melting adhesive, heating the laminate sheet at a forming temperature, and forming the heated laminate sheet by using a male and female molds arranged with a certain space, characterized in that the container main body and the breathable inner body are separated with a prescribed distance from each other by vacuum suction through the female mold or by air pressure through the male mold. On account of the double wall structure, the container prevents the content from becoming sticky and deteriorated and keeps the content fresh.

Abstract: An apparatus for thermoforming articles out of a sheet plastic material includes a female mold having one or more cavities and a male mold including one or more plug assists in one to one correspondence with the female mold cavities. Each cavity of the female mold communicates with a first passageway. A vacuum source communicates with each first passageway, and includes a vacuum switch. Each plug assist is provided with one or more inlets extending through the plug assist and one or more second passageways, the second passageways and inlets each communicating with the respective cavities when the mold is in a closed position. A first air source communicates with the inlet and includes a first heating means and a switch to selectively apply heated air through the inlet into the cavity under pressure.

Abstract: The method for thermoforming articles out of a sheet of plastic material including initially applying a negative pressure to the cavity and a first forming gas to the second side of the sheet facing the male mold section, switching to a second pressurizing gas for a period of time to allow a level of crystallization of the conformed sheet, and flowing a cooling stream of gas against the sheet to arrest further crystallation.

Abstract: A method of forming relatively large objects, such as refrigerator liners, by a solid phase forming process from crystalline-type synthetic resins, such as polypropylene. The invention comprehends utilization of stretch forming, vacuum forming, and pressure forming techniques in combination with controlled heating of different portions of the billet to provide desired differential thicknesses in different portions of the liner. The invention further comprehends the provision of the liner with biaxial molecular orientation in portions thereof subject to shock impact forces.

Abstract: The present invention concerns an apparatus and method for thermoforming a plastic article from a sheet of plastic material heated to a predetermined forming temperature. The apparatus includes a mold having forming surfaces defining a forming cavity generally conforming to the shape of the plastic article to be formed. The heated plastic sheet is urged into contact with the forming surfaces of the mold to form the plastic article. The mold includes at least one undercut forming element moveable between an advanced position wherein the element projects into the forming cavity to form an undercut portion in the plastic article and a retracted position wherein the element is withdrawn from the forming cavity to enable the formed plastic article to be removed from the forming cavity. After the plastic article has been formed, the undercut forming element is moved to the retracted position and a stripper plate is utilized to remove the formed plastic article from the forming cavity.

Abstract: The present invention is directed to an apparatus for the production of back-foamed covers from cover materials and foam comprising(i) a mold comprising an upper mold half and a lower mold half, the lower mold half having a cavity therein, the inside surface of which is capable of being covered by the cover material,(ii) a mixhead associated with the mold, the mixhead capable of introducing foam materials and/or reactants into the mold cavity,(iii) a pusher bar arranged on a mount for pushing the cover material into the mold cavity and being arranged above the lower mold half, the pusher bar being constructed such that when the bar is pushing the cover material into the mold cavity, a gap is formed between the edge of the mold cavity and the edge of the pusher bar, the gap being less than the thickness of the cover material,(iv) the lower mold half being movable towards and/or away from the pusher bar, and(v) the surface of the pusher bar facing the mold cavity edge being a frictional surface.

Abstract: An improved method and apparatus for rapidly forming plastic foam shells from a flexible foam sheet. The foam sheet is intermittently passed through a radiant heating unit and is rapidly heated on both sides to 130.degree.-250.degree. F. to soften the foam. The heated foam sheet is immediately passed through a forming die unit in which the foam sheet is deformed partly into the die cavity by withdrawal of air from the cavity, and a die plug descends and final forms a shell while rapidly cooling the foam shell to below its plastic deformation temperature. By this forming method and apparatus, ethylene-containing foam shells having a depth 10-25 times the foam sheet initial thickness are rapidly formed at 10-30 cycles/minute.

Abstract: Apparatus for forming deep containers from a thermoplastic material including a first mold portion having a cavity therein defining the side and bottom configuration of the container and a second mold portion having a plunger provided for reciprocation therein and arranged so that the plunger moves into the cavity. The first mold portion is provided with a first passageway that terminates adjacent to the cavity and in the parting surface of the mold portion and a second passageway that extends therethrough into the cavity adjacent to the bottom of the container. A control apparatus is provided that directs a vacuum through the first passageway securely holding the thermoplastic against the parting surface of the first mold portion.

Abstract: A process and apparatus for pneumatic-pressure forming or vacuum/pneumatic-pressure forming a web of thermoplastic material into a matrix form of containers and having the thus-formed plastic product processed with a thermal fixation operation, which comprises in combination the steps of holding a forming mold at a thermal fixing temperature for the plastic to be formed so as to have the matrix of containers thermally fixed through a temperature range characteristic of the plastic; and cooling-off thus-formed plastic containers, while maintaining the interior of the formed plastic containers at such a pressure level that the formed plastic containers are no longer subjected to any risk of deformation after the forming mold is removed, and after having been removed from the engagement with the forming mold.

Abstract: A process for forming hollow articles from a thermoplastic polymer sheet material. Polymer sheet material is heated to a forming temperature and clamp between a ported mold plug and a jacketed mold cavity. The mold plug is moved into the mold cavity to stretch the material into the cavity. The clamping is released during the moving of the plug and a substantial portion of the air trapped between the material and mold cavity is evacuated. Pressurized forming gas is injected through flow means around the mold plug to further expand the material into the mold cavity. Thereafter, the injecting of forming gas is discontinued and coolant is flowed through the jacketed mold cavity and a cooling fluid is injected through the ported mold plug against the material while the pressurized forming gas is simultaneously purged from the area between the mold plug and expanded material through the flow means.

Abstract: A method for double-side thermoforming opposite faces of a sheet of plastic is set forth. The method includes heating the sheet to a temperature within its transition range and forming one face of the sheet into the desired pattern by bringing a contour-forming first surface into contact with the face. After contact has been made, a pressure differential is imposed to cause the one face to be formed by and freeze-off to the contour of the first surface. After one face of the sheet has been formed, a second contour-forming surface is positioned adjacent to the other face of the plastic sheet. Producing a pressure differential between the opposite faces of the plastic sheet causes the other face to be formed by and freeze-off into the desired pattern imposed by the second contour-forming surface resulting in the desired plastic part. The present invention also includes a plastic part fashioned according to the aforesaid method.

Abstract: Disclosed is a process of making an oriented and heat set thermoformed hollow article of poly(ethylene terephthalate) so that the sidewalls of the articles resulting from the process have a density over 1.391 cc./gm. and an onset-of-shrinkage temperature over 105.degree. C. In the process, a sheet preheated to a temperature suitable for orientation is biaxially stretch thermoformed and then while the hollow article walls are still in contact with the mold walls, the article is raised to a higher heat setting temperature in the range of about 220-250.degree. C. thus heat setting the article, and while the article is still under restraint resisting shrinkage, quenching the sidewalls of the article to a temperature that will provide a shrinkage of less than about 5% by volume and the above onset-of-shrinkage temperature of at least about 105.degree. C.

Abstract: The process for making thin wall containers from plastic resins described herein includes the step of heating the resin, placing the resin between a product mold and a preform mold, and closing the molds thereon. It also includes the steps of applying a differential pressure across the resin to force the resin into the preform mold and applying pressure on a movable piston in the preform mold that forces the resin relatively into the product mold. As pressure is applied internally of the product being formed, the container is shaped in the desired configuration and during such formation, is biaxially oriented to improve the strength characteristics of the container.