WO2002036323A9 - Buse a obturateur pour moulage par co-injection avec chemins d'ecoulement de matiere separes - Google Patents

Buse a obturateur pour moulage par co-injection avec chemins d'ecoulement de matiere separes

Info

Publication number
WO2002036323A9
WO2002036323A9 PCT/US2001/046230 US0146230W WO0236323A9 WO 2002036323 A9 WO2002036323 A9 WO 2002036323A9 US 0146230 W US0146230 W US 0146230W WO 0236323 A9 WO0236323 A9 WO 0236323A9
Authority
WO
WIPO (PCT)
Prior art keywords
passageway
bushing
cavity
mold cavity
plastic material
Prior art date
Application number
PCT/US2001/046230
Other languages
English (en)
Other versions
WO2002036323A1 (fr
WO2002036323B1 (fr
Inventor
Eric J Seres Jr
Scott R Greb
Original Assignee
Incoe Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Incoe Corp filed Critical Incoe Corp
Priority to AU2002228761A priority Critical patent/AU2002228761A1/en
Publication of WO2002036323A1 publication Critical patent/WO2002036323A1/fr
Publication of WO2002036323B1 publication Critical patent/WO2002036323B1/fr
Publication of WO2002036323A9 publication Critical patent/WO2002036323A9/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/16—Making multilayered or multicoloured articles
    • B29C45/1603—Multi-way nozzles specially adapted therefor

Definitions

  • the present invention relates to pin-type valve-gate bushing devices for use with co-injection molding systems .
  • Co-injection systems are often also called co-extrusion systems.
  • co-injection or co- extrusion systems inject two different materials, typically an inner core material and an outer skin material, into a single or multiple-cavity mold.
  • the outer skin material typically enters the cavity first and the core material is injected into the center of the skin layer forcing the skin material against the walls of the cavity.
  • Co-injection systems enable the use of less expensive materials as the core material, and thus can significantly lower the cost of molded products .
  • a valve-gate bushing is provided with a pin-type material shutoff mechanism.
  • the bushing has two separate passageways for flow of the core and skin materials into the mold cavity, as well as a separate passageway for the valve pin.
  • the pin-type valve-gate device easily and effectively opens and closes the flow of the two plastic materials into the mold cavity as desired.
  • the bushing has an actuation mechanism which operates a pin member to selectively open and close the bushing orifice, as well as the two plastic material passageways.
  • the movable elongated pin member is, movable between at least three positions.
  • a piston-type actuation mechanism which is operated either hydraulically, electrically, pneumatically, or the like, selectively moves the pin member longitudinally to open and close the bushing orifice and the two plastic material passageways.
  • the end of the pin member mates with the orifice in the end of the bushing or nozzle member creating a valve or "gate" for entry of the plastic materials into the mold cavity.
  • the pin member can also be moved longitudinally away from the orifice in order to allow selective passage of the two plastic materials forming the skin and core of the molded part .
  • a pair of movable piston members are positioned in the actuation (control) mechanism.
  • the elongated pin member is adjustably attached to one of the piston members.
  • the two piston members are moved together or independently, thus resulting in the desired movement of the pin member relative to the orifice and the two plastic material passageways.
  • FIGURE 1 schematically illustrates a preferred embodiment of the present invention
  • FIGURES 2 and 3 are plan and side views, respectively, of the embodiment shown in Figure 1;
  • FIGURES 4-6 illustrate the three main positions of the piston and pin members, and also depict the operation of the preferred embodiment of the invention.
  • Figures 1-3 illustrate a preferred embodiment of the present invention
  • Figures 4-6 illustrate its use in a co-injection plastic molding process.
  • the inventive system is referred to generally by the reference numeral 10 in the drawings.
  • the system 10 includes a bushing member 12, a manifold 14, and a cylinder or block member 16.
  • the mold bushing 12 which is sometimes referred to as a "nozzle," is mounted in a cavity 18 in a mold 20.
  • the mold 20 can be of any conventional type and has a first plate member 22 in which the bushing 12 is at least partially positioned, as well as a second plate member 24 which has a mold cavity 26 therein.
  • the sprue bushing or nozzle 12 has a metal body or shank member 30, an external heater member 32, and a screw on tip member 34.
  • the tip member 34 has a forward end 36 which is adapted to fit within the end of the recess 18.
  • the end of the recess 18 forms an orifice or "gate" 42 through which the plastic material flows into the mold cavity 26.
  • the body member 30 has three elongated passageways 44, 46, and 48 formed therein.
  • Passageway 44 is for injection of the core material 50 into the cavity, while passageway 48 is for injection of the plastic skin material 52 into the mold cavity.
  • Passageway 46 is centrally located in the body member
  • the pin member 60 is positioned in it.
  • the pin member 60 has an upper end 62 and a lower end 64 and is positioned in the passageway 46.
  • the pin member 60 is movably positioned inside the elongated passageway 46 in the body 30 of the bushing 12.
  • the upper end 62 of the pin member 60 is secured to piston member 70 in the actuator mechanism 71 positioned in the block member 16.
  • the actuator mechanism 71 includes a pair of piston members, 70 and 72, which are slidably positioned in a cylindrical cavity 74.
  • the upper end 62 of the pin member 60 is threadedly attached to a threaded internal bore 76.
  • the open end 78 of the bore 76 allows adjustment of the position of the pin member 60 relative to the piston member 70 by use of an appropriate tool, such as a screwdriver. If desired, a cap or plug member 80 can be provided to cover the openings in the block and protect . the open end 78 from dust, oil and other undesirable matters.
  • the cavity 74 is enclosed by a cover or cap member 82.
  • the cap member 82 is fastened to the block member 16 by a plurality of bolts, screws, or other fasteners 84, only one of which is shown in the drawings .
  • Appropriate seals are provided in the actuator mechanism 71 in order to allow accurate movement of the piston members 70 and 72 in the chamber 74 without leakage of pressurized fluid.
  • a plurality of seal members are provided.
  • the seal members are generally designated by the letter “S" in Figure 1 and can be of any conventional type used with pressurized and/or hydraulic systems known today.
  • the piston members 70 and 72 are slidably positioned in the chamber cavity 74 and used to operate the movement of the pin member 60 in the bushing member 12.
  • a pressurized fluid such as a liquid or gas, is introduced into portions or areas of the chamber cavity 74 by channels 86, 88, and 90, as desired, and provide movement of the pistons 70 and 72.
  • the precise movement of the piston members and resulting movement of the pin member 60 are described in more detail below.
  • the bushing member 12 is attached to or secured to the manifold 14 in any conventional manner.
  • the manifold 14, together with the mold plates 22 and 96 are tightly clamped together.
  • the manifold 14 has passageway 100 for passage of the plastic core material from an injection molding machine "IM-B" into the bushing 12 and, in turn, into the mold cavity 26.
  • the manifold 14 also has passageway 102 for passage of the skin material from an injection molding machine "IM-A" and into the bushing 12 and mold cavity 26.
  • the passageways 100 and 102 are aligned with passageways 44 and 48, respectively, in the bushing member 12.
  • Appropriate seals are provided in grooves 104 at the interface between the body member 30 of the bushing 12 and the lower surface of the manifold member 14.
  • the heater member 32 can be of any conventional type and is used to maintain the plastic material in the passageways 44 and 48 in the bushing 12 in a molten condition.
  • the heater member 32 is typically a resistance-type heating member or element and is energized through lead or connector member 33.
  • the tip member 34 is preferably threadedly secured to the lower end of the body member 30 of the bushing member 12.
  • An insert member 36, secured by tip member 34 has connecting passageways 44A and 48A, which are aligned with the passageways 44 and 48 in the body member 30.
  • the lower end ' 44B of passageway 44A connects with and opens into the passageway 46 in which the pin member 60 is positioned.
  • the lower end 48B of passageway 48A connects to and opens into the passageway 46.
  • the ends 44B and 48B open into the central passageway 46 at positions which are spaced longitudinally or axially relative to one another. This allows entry of the skin and core material into the central passageway 46 and thus through the orifice 42 and into the mold cavity 26 separately as desired during the molding process.
  • the entry of the plastic material into the mold cavity is controlled by movement of the pin member 60.
  • the piston members 70 and 72 in the actuator mechanism 71 are operated to longitudinally move the lower end 64 of the pin member 60 in at least three positions. Hydraulic or pneumatic fluid or gas is supplied to the passageways 86, 88, and 90 from one or more conventional hydraulic or pneumatic power sources (not shown) . If desired, the passageways can all be connected to the same pressure source and selectively utilized by an appropriate valving and control system.
  • Passageways 86, 88, and 90 are machined or provided in the cylinder block 16 and cover member 82 in the positions shown in Figures 1 and 4-6, although it is understood that they can be provided in other locations within the skill of persons in the art.
  • the lower end 64 of pin member 60 is adapted to mate with the opening 42 (orifice) of the bushing 12 and form a valve-gate mechanism.
  • the valve or gate into the mold cavity is initially its closed position, as closed in Figure 4. In this condition, plastic material present in the manifold 14 and bushing 12 is prevented from entering into the mold cavity.
  • pressurized fluid is introduced into cavity 74 through passageway 88. This causes the piston member 70 to be moved toward the lower end 74A of the cavity 74 , thereby causing the lower end 64 at the pin member 60 to enter into and close the orifice 42.
  • the pin member 60 is raised an additional amount in the central passageway 46 in order to allow passage of the plastic core material into the mold cavity. This is shown in Figure 6.
  • the end 64 of the pin member 60 is raised sufficiently to allow injection of plastic material in passageways 44, 44A and 44B into the central passageway 46 and into the mold cavity.
  • pressurized fluid is continued to be introduced through passageway 86.
  • pressurized fluid in chamber 74 which had been provided through passageway 90 is relieved or exhausted through passageway 90.
  • pistons 70 and 72 are both moved longitudinally upwardly as viewed in Figure 6 which, in turn, pulls the pin member 60 in an upward direction, opening passageway 44B.
  • the molded part in accordance with the present process has an outer skin layer 52 and an inner core layer 50.
  • the molded part is allowed to cool in the mold until it becomes solid and hard. Thereafter, the mold is opened and the formed part is ejected. Thereafter, the cycle is repeated and additional co-extruded molded parts are formed.
  • the skin material Upon entering the mold cavity, the skin material will develop a flow front through the cavity toward the end walls thereof. As the skin material contacts the cold walls of the mold, it begins to solidify, developing a solid outer layer. Before skin material reaches the end of the cavity, however, the core material is injected into the part to form the core. The core material develops a second flow front and pushes the skin material ahead of it . The core material expands and pushes the skin material outwardly until the entire mold cavity is filled.
  • An advantage of co-injection molding is the use of a core material having a different material than the skin material which appears visible on the molded part. Co-injection enables the use of less expensive materials as the core material, and can lower part cost substantially.
  • the pressures are maintained to compensate for any volumetric shrinkage of the plastic as it cools and solidifies.
  • the mold members 12 and 24 are typically cooled by circulation of a coolant through appropriate channels or passageways (not shown) which assist in solidifying the plastic.
  • the plastic materials are introduced into the manifold 12 from two different injection molding machines, IM-A and IM-B.
  • injection molding machine IM-A is used to inject the skin material into the manifold 14 for formation of the molded part in the mold cavity 26.
  • adapter member 110 is used to orient injection molding machine IM-A relative to the plate member 96.
  • a nozzle bushing 112 is utilized to permit passageway of the plastic material from the injection molding machine into the passageway 102 in the manifold member 14.
  • the nozzle seat has a significant length, it is preferable to use a heater member, such as the coil heater member 114, in order to maintain the plastic material in a molten condition in the passageway 116 in the nozzle seat 112.
  • the heater member 114 is typically a resistance-type heating member or element and is energized by a connector or lead 118.
  • the injection molding machine IM-B is similarly attached to and arranged with the system 10. As shown in Figures 2 and 3, the injection molding machine IM-B is connected to mold plate 93 through adapter member 120 and nozzle seat 122.
  • the nozzle seat 122 has a heater member 124 thereon.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Moulds For Moulding Plastics Or The Like (AREA)

Abstract

L'invention concerne un appareil et des procédés de co-injection de matières plastiques. Deux matières plastiques sont injectées dans la cavité du moule (26) par l'intermédiaire de passages séparés (44, 48) situés dans un élément de buse (12). Un élément de broche (60) situé dans un troisième passage (46) à l'intérieur de la buse du moule permet de réguler l'introduction des deux matières plastiques dans la cavité par l'intermédiaire d'un orifice (42). Un mécanisme d'actionnement (71) comportant des pistons actionnés par pression (70, 72) commande le mouvement cet élément de broche.
PCT/US2001/046230 2000-10-31 2001-10-23 Buse a obturateur pour moulage par co-injection avec chemins d'ecoulement de matiere separes WO2002036323A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2002228761A AU2002228761A1 (en) 2000-10-31 2001-10-23 Co-injection valve-gate bushing with separate material flow paths

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US70257700A 2000-10-31 2000-10-31
US09/702,577 2000-10-31

Publications (3)

Publication Number Publication Date
WO2002036323A1 WO2002036323A1 (fr) 2002-05-10
WO2002036323B1 WO2002036323B1 (fr) 2003-05-22
WO2002036323A9 true WO2002036323A9 (fr) 2004-03-04

Family

ID=24821795

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2001/046230 WO2002036323A1 (fr) 2000-10-31 2001-10-23 Buse a obturateur pour moulage par co-injection avec chemins d'ecoulement de matiere separes

Country Status (2)

Country Link
AU (1) AU2002228761A1 (fr)
WO (1) WO2002036323A1 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ITMI20020593A1 (it) * 2002-03-20 2003-09-22 Enrico Scarabelli Procedimento per lo stampaggio ad iniezione di prodotti in almeno duemateriali distinti
DE102006005643A1 (de) * 2006-02-08 2007-08-09 Mht Mold & Hotrunner Technology Ag Heisskanalnadelventil

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5650178A (en) * 1994-11-23 1997-07-22 Bemis Manufacturing Company Co-injection manifold for injection molding
US6062840A (en) * 1997-09-02 2000-05-16 Dynisco Hotrunners, Inc. Hot runner system for coinjection molding
CA2219235C (fr) * 1997-10-23 2006-12-12 Mold-Masters Limited Appareil de moulage par injection de cinq couches ayant un actionneur de soupape a quatre positions

Also Published As

Publication number Publication date
WO2002036323A1 (fr) 2002-05-10
AU2002228761A1 (en) 2002-05-15
WO2002036323B1 (fr) 2003-05-22

Similar Documents

Publication Publication Date Title
CA2878559C (fr) Appareil de moulage par coinjection et buse d'injection chauffee correspondante
EP1021286B1 (fr) Douille a obturateur assistee par fluide munie d'aiguilles concentriques
EP0163083B1 (fr) Orifice d'injection annulaire à noyau à ouverture périphérique pour le moulage par injection
US5204050A (en) Gas assisted injection molding
US5423672A (en) Molding device having a ring-gating and hole forming valve gate pin
EP0400135B1 (fr) Procédé de moulage par injection
EP0462969B1 (fr) Procede et system pour fabriquer un corps creux a partir de resine en fusion par moulage par injection
US5273707A (en) Method of injection molding
EP0452611B1 (fr) Buse d'injection avec une torpille chauffée à mouvement alternatif
US5458846A (en) Method of injection molding
US20040018266A1 (en) Metering device for a plastics moulding machine
US20080093773A1 (en) Reverse Motion Valve Gating System
US20060159798A1 (en) Method for producing mould parts by injection and plugged needle nozzle for an injection mould
WO2002036323A9 (fr) Buse a obturateur pour moulage par co-injection avec chemins d'ecoulement de matiere separes
US4913644A (en) System for making a hollow-shaped body from molten resin by injection molding
EP0624122B1 (fr) Dispositif et procede de moulage par injection au moyen d'injection de gaz
MXPA99006131A (en) Fluid assist valve-gate bushing with concentric pin members
JPH0124052B2 (fr)

Legal Events

Date Code Title Description
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
B Later publication of amended claims

Free format text: 20020524

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
COP Corrected version of pamphlet

Free format text: PAGES 1-12, DESCRIPTION, REPLACED BY NEW PAGES 1-12; PAGES 13-16, CLAIMS, REPLACED BY NEW PAGES 13-16; PAGES 1/3-3/3, DRAWINGS, REPLACED BY NEW PAGES 1/3-3/3; DUE TO LATE TRANSMITTAL BY THE RECEIVING OFFICE

NENP Non-entry into the national phase in:

Ref country code: JP