WO2008087484A1 - Method for injection molding of hollow articles of plastic material - Google Patents

Method for injection molding of hollow articles of plastic material Download PDF

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Publication number
WO2008087484A1
WO2008087484A1 PCT/IB2007/004123 IB2007004123W WO2008087484A1 WO 2008087484 A1 WO2008087484 A1 WO 2008087484A1 IB 2007004123 W IB2007004123 W IB 2007004123W WO 2008087484 A1 WO2008087484 A1 WO 2008087484A1
Authority
WO
WIPO (PCT)
Prior art keywords
plunger
cavity
channel
duct
injection
Prior art date
Legal status (The legal status 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 status listed.)
Ceased
Application number
PCT/IB2007/004123
Other languages
French (fr)
Inventor
Elmar Fries
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ITW Automotive Products GmbH
Original Assignee
ITW Automotive Products GmbH
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 ITW Automotive Products GmbH filed Critical ITW Automotive Products GmbH
Priority to EP07859200A priority Critical patent/EP2117801A1/en
Priority to US12/513,580 priority patent/US7998395B2/en
Publication of WO2008087484A1 publication Critical patent/WO2008087484A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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
    • B29C45/17—Component parts, details or accessories; Auxiliary operations
    • B29C45/1703—Introducing an auxiliary fluid into the mould
    • B29C45/1704—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles
    • B29C45/1711—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles and removing excess material from the mould cavity by the introduced fluid, e.g. to an overflow cavity
    • 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
    • B29C45/17—Component parts, details or accessories; Auxiliary operations
    • B29C45/38—Cutting-off equipment for sprues or ingates
    • 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
    • B29C45/17—Component parts, details or accessories; Auxiliary operations
    • B29C45/1703—Introducing an auxiliary fluid into the mould
    • B29C45/1704—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles
    • B29C45/1711—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles and removing excess material from the mould cavity by the introduced fluid, e.g. to an overflow cavity
    • B29C2045/1712—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles and removing excess material from the mould cavity by the introduced fluid, e.g. to an overflow cavity plastic material flowing back into the injection unit
    • 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
    • B29C45/17—Component parts, details or accessories; Auxiliary operations
    • B29C45/1703—Introducing an auxiliary fluid into the mould
    • B29C45/1704—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles
    • B29C2045/1718—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles sealing or closing the fluid injection opening
    • 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
    • B29C45/17—Component parts, details or accessories; Auxiliary operations
    • B29C45/26—Moulds
    • B29C45/27—Sprue channels ; Runner channels or runner nozzles
    • B29C45/28—Closure devices therefor

Definitions

  • the present invention relates to an injection molding method for plastic, hollow molded articles.
  • the present invention also relates to an injection mold to make hollow molded articles.
  • the molded articles After it has been removed from the injection mold, the molded articles comprises two apertures leading to the mold cavity, one aperture being constituted by the gas nozzle and the other by the hollow duct in the sprue which must be severed from the molded article.. If such a molded article must be processed further, in particular in electroplating equipment, to fitted with metal coating(s), said apertures must be mandatorily sealed. Sealing the gas intake aperture raises no problems because a specific, geometric structure is involved and therefore an appropriate stopper may be used. On the other hand problems are encountered with the other aperture. The latter case inevitably entails further processing steps to seal the hollow molded articles against fluid leakage.
  • the objective of the present invention is to create a method implementing full sealing of a hollow, injection molded article without entailing additional finishing or resort to a further injection molding implement.
  • a specific quantity of flowable plastic is moved, by a power-driven plunger from a blind duct communicating with the runner duct into this runner duct.
  • the plastic in the blind duct moves into the runner duct in the sprue and partly back into the molded article's hollow. In this manner, the molded article's aperture is sealed off completely.
  • the method of the present invention allows sealing the molded article's cavity aperture in one step jointly with the making of the part in the injection mold.
  • the runner duct must be removed from the molded article.
  • the molded article's runner duct is separated from it using the plunger.
  • the plunger or the blind duct may be heated, for instance, by an appropriate electrical heater.
  • the injection molding equipment of the present invention to manufacture a hollow molded article comprises a blind duct which is connected to the runner duct comparatively close to the mold cavity.
  • the bottom of the blind duct is constituted by the plunger which — as already mentioned -- is driven by a power element.
  • this power element is a pneumatic or hydraulic cylinder.
  • the plunger When the plunger is used to force the material out of the blind duct into the runner duct, part of said material migrates toward the mold cavity, sealing said cavity's aperture at the junction with the runner duct.
  • the said aperture is completely sealed off in this manner, and as a result, even after ejecting the molded article and severing the runner duct, the mold cavity shall be impermeably sealed.
  • the plunger surface facing the runner duct is oblique relative to the mold cavity. In this manner more material is forced toward the mold cavity than in the opposite direction in what remains of the runner duct.
  • the plunger may be a cutting or severing tool to separate the runner duct from the molded article.
  • Appropriately recesses complementary to the plunger shape may be constituted in the runner duct wall on the side opposite the blind duct to receive the plunger when it forces material out of the blind duct and as applicable also separates the runner duct.
  • Fig. 1 schematically shows manufacturing a molded article in an injection mold, following evacuation of a middle zone using compressed gas
  • Fig. 2 shows the configuration of Fig. 1 after a portion of the evacuated material has been forced back into the mold cavity.
  • Figs. 1 and 2 show an injection mold 10.
  • Said mold illustratively is constituted by two mold halves which are selectively joined to each other to define a mold cavity 12 or to be moved apart in order to eject a molded article.
  • the mold cavity 12 communicates with a runner duct 14 leading to a sprue 16a.
  • this sprue 16a communicates with an extruder from which flowable plastic is injected through the sprue 16a into the mold cavity 12
  • the injected material is denoted by 16.
  • pressurized gas is introduced through a so-called (omitted) gas needle into the mold cavity 12 as indicated by the arrow 18.
  • partly set material 16 is evacuated from the mold cavity 12 and forced back into the duct 14.
  • a hollow 20 of the molded part is constituted which extends into the duct 14 by means of a hollow channel 22.
  • the duct 14 communicates with a transverse duct. It is sealed off by a plunger 26 to define a blind duct 24.
  • the plunger 26 is driven by a power element and, as indicated in Fig. 2, it can be adjusted toward the duct 14 as indicated by the arrow 28.
  • the blind duct 24 may be heated by an electric heater 30.
  • the plunger 26 may be fitted with a heater element 34 to raise the temperature of the plunger 26.
  • the blind duct 24 is filled with flowable material 16 during injection molding.
  • the plunger 26 is operated as indicated in Fig. 2, the flowable material is forced out of the blind duct 24 and toward the duct 14 and, as a result, it is displaced along both sides of this duct 14 as illustrated at 36 and
  • the plunger 26 is fitted with an end face 38a, oblique to the mold cavity 12, so that, when said plunger is actuated, more flowable material 16 is displaced toward the mold cavity 12 than in the opposite direction. In this manner a lug or stopper 40 is formed in the molded article's aperture - that was formed by the introduction of gas - which completely seals said cavity off duct 14.
  • the duct 14 too can be separated from the molded article using the plunger 26.
  • the duct 14 may be fitted with a recess 42 (shown in dashed lines) which is complementary to the plunger 26 and situated in the wall opposite the blind duct 24.
  • the duct 14 may be terminated conventionally, in which case a rupturing site 44 would be shaped into it.

Landscapes

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

Abstract

An injection molding method to manufacture hollow plastic parts, whereby at least one plastic part's hollow is shaped by evacuating an internal portion of the flowable material of an injection mold's cavity (12) using a pressurized gas and a gate of said mold (10) and thereupon the molded article's aperture so made shall be sealed off, characterized in that, following said flowable material's being removed from a blind duct (24) into a gate branched to it and after being partly forced back into said hollow, said molded article shall be elected from the injection mold (10).

Description

METHOD FOR INJECTION MOLDING OF HOLLOW ARTICLES OF PLASTIC MATERIAL
The present invention relates to an injection molding method for plastic, hollow molded articles.
Moreover the present invention also relates to an injection mold to make hollow molded articles.
The manufacture of molded plastic articles using injection molding is common state of the art. Moreover it is known to make hollow molded articles in a manner that following introduction of the flowable plastic into the injection mold cavity, pressurized gas shall be applied that shall evacuate a portion of the flowable plastic from the mold cavity through the runner duct.
After it has been removed from the injection mold, the molded articles comprises two apertures leading to the mold cavity, one aperture being constituted by the gas nozzle and the other by the hollow duct in the sprue which must be severed from the molded article.. If such a molded article must be processed further, in particular in electroplating equipment, to fitted with metal coating(s), said apertures must be mandatorily sealed. Sealing the gas intake aperture raises no problems because a specific, geometric structure is involved and therefore an appropriate stopper may be used. On the other hand problems are encountered with the other aperture. The latter case inevitably entails further processing steps to seal the hollow molded articles against fluid leakage.
The objective of the present invention is to create a method implementing full sealing of a hollow, injection molded article without entailing additional finishing or resort to a further injection molding implement. In the method of the present invention, a specific quantity of flowable plastic is moved, by a power-driven plunger from a blind duct communicating with the runner duct into this runner duct. In this manner, the plastic in the blind duct moves into the runner duct in the sprue and partly back into the molded article's hollow. In this manner, the molded article's aperture is sealed off completely.
Accordingly, the method of the present invention allows sealing the molded article's cavity aperture in one step jointly with the making of the part in the injection mold.
It is known that the runner duct must be removed from the molded article. In one embodiment mode of the present invention, the molded article's runner duct is separated from it using the plunger.
In order that the material within the blind duct be sufficiently flowable, the plunger or the blind duct may be heated, for instance, by an appropriate electrical heater.
The injection molding equipment of the present invention to manufacture a hollow molded article comprises a blind duct which is connected to the runner duct comparatively close to the mold cavity. The bottom of the blind duct is constituted by the plunger which — as already mentioned -- is driven by a power element. Illustratively this power element is a pneumatic or hydraulic cylinder. When manufacturing the injection molded article of the invention, the runner duct and the blind duct are filled up with a flowable material. A pressurized gas is introduced and an internal region of the flowable material within the mold cavity is removed through the runner duct, as a result of which a hollow duct of more or less pronounced length is constituted in that runner duct and extends through the blind duct and beyond. When the plunger is used to force the material out of the blind duct into the runner duct, part of said material migrates toward the mold cavity, sealing said cavity's aperture at the junction with the runner duct. The said aperture is completely sealed off in this manner, and as a result, even after ejecting the molded article and severing the runner duct, the mold cavity shall be impermeably sealed.
In one embodiment mode of the present invention, the plunger surface facing the runner duct is oblique relative to the mold cavity. In this manner more material is forced toward the mold cavity than in the opposite direction in what remains of the runner duct.
In another embodiment mode of the present invention, the plunger may be a cutting or severing tool to separate the runner duct from the molded article. Appropriately recesses complementary to the plunger shape may be constituted in the runner duct wall on the side opposite the blind duct to receive the plunger when it forces material out of the blind duct and as applicable also separates the runner duct.
The invention is elucidated below in relation to the appended drawings.
Fig. 1 schematically shows manufacturing a molded article in an injection mold, following evacuation of a middle zone using compressed gas, and
Fig. 2 shows the configuration of Fig. 1 after a portion of the evacuated material has been forced back into the mold cavity.
Figs. 1 and 2 show an injection mold 10. Said mold illustratively is constituted by two mold halves which are selectively joined to each other to define a mold cavity 12 or to be moved apart in order to eject a molded article. The mold cavity 12 communicates with a runner duct 14 leading to a sprue 16a. Illustratively this sprue 16a communicates with an extruder from which flowable plastic is injected through the sprue 16a into the mold cavity 12 In Fig.
2, the injected material is denoted by 16. In a gas internal pressure procedure, pressurized gas is introduced through a so-called (omitted) gas needle into the mold cavity 12 as indicated by the arrow 18. In this manner, partly set material 16 is evacuated from the mold cavity 12 and forced back into the duct 14. In this manner, a hollow 20 of the molded part is constituted which extends into the duct 14 by means of a hollow channel 22.
Near the mold cavity 12, the duct 14 communicates with a transverse duct. It is sealed off by a plunger 26 to define a blind duct 24. The plunger 26 is driven by a power element and, as indicated in Fig. 2, it can be adjusted toward the duct 14 as indicated by the arrow 28.
The blind duct 24 may be heated by an electric heater 30. Moreover, the plunger 26 may be fitted with a heater element 34 to raise the temperature of the plunger 26.
The blind duct 24 is filled with flowable material 16 during injection molding. When the plunger 26 is operated as indicated in Fig. 2, the flowable material is forced out of the blind duct 24 and toward the duct 14 and, as a result, it is displaced along both sides of this duct 14 as illustrated at 36 and
38, respectively. The plunger 26 is fitted with an end face 38a, oblique to the mold cavity 12, so that, when said plunger is actuated, more flowable material 16 is displaced toward the mold cavity 12 than in the opposite direction. In this manner a lug or stopper 40 is formed in the molded article's aperture - that was formed by the introduction of gas - which completely seals said cavity off duct 14.
The duct 14 too can be separated from the molded article using the plunger 26. Appropriately the duct 14 may be fitted with a recess 42 (shown in dashed lines) which is complementary to the plunger 26 and situated in the wall opposite the blind duct 24.
Alternatively the duct 14 may be terminated conventionally, in which case a rupturing site 44 would be shaped into it.

Claims

1. A method for injection molding of a hollow part of plastic material, whereby a cavity of the hollow part is shaped by evacuating an internal portion of the flowable plastic material in a cavity of an injection mold by using pressurized gas whereby the material is pressed into a runner duct of the mold, characterized in that after pressing the material into the runner duct, the material is partially forced back into the cavity of the hollow part by means of a power actuated plunger located in a blind channel which is connected to the runner duct.
2. A method of claim 1 , wherein a lug formed by the forced back material is separated from the part by means of the plunger.
3. A method of claim 1 or 2, wherein the plunger and/or the blind channel is heated.
4. A method of claim 1 , wherein the lug of the part is formed with a breaking point.
5. An injection mould for the manufacture of an article having at least one hollow space, comprising a preferably split injection tool having at least one cavity, the cavity being connected to a casting channel through which plasticized mass is pressed into the mould cavity, and a gas passage through which gas under pressure is supplied into the mould cavity to remove an inner portion of the plasticized mass from the mould cavity through the casting channel, characterized in that adjacent to the mould cavity (12), a blind channel (24) is formed connected to the casting channel (14), the bottom of the blind channel being formed by a plunger (26) within the blind channel and the plunger (26) being actuable by power means to move the plunger towards the casting channel (14).
6. The injection mould of claim 5, wherein a surface of the plunger facing the casting channel (14) is inclined relative to the casting channel (14).
7. The injection mould of claim 5 or 6, wherein the plunger (26) includes electrical heating means (34).
8. The injection mould of claim 5, wherein electrical heating means (30) are associated with the blind channel (24).
9. The injection mould of claim 6, wherein the plunger (26) is formed as a cutting or separating tool.
10. The injection mould of claim 9, wherein the wall of the casting channel (14) opposite to the blind channel (24) has a recess (42) complementary to the shape of the plunger (26) for receiving the associated plunger's portion upon its movement into the casting channel (24).
PCT/IB2007/004123 2007-01-11 2007-12-27 Method for injection molding of hollow articles of plastic material Ceased WO2008087484A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP07859200A EP2117801A1 (en) 2007-01-11 2007-12-27 Method for injection molding of hollow articles of plastic material
US12/513,580 US7998395B2 (en) 2007-01-11 2007-12-27 Method for injection molding of hollow articles of plastic material

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102007001756A DE102007001756B4 (en) 2007-01-11 2007-01-11 Method and injection mold for injection molding of hollow molded plastic parts
DE102007001756.3 2007-01-11

Publications (1)

Publication Number Publication Date
WO2008087484A1 true WO2008087484A1 (en) 2008-07-24

Family

ID=39327448

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2007/004123 Ceased WO2008087484A1 (en) 2007-01-11 2007-12-27 Method for injection molding of hollow articles of plastic material

Country Status (5)

Country Link
US (1) US7998395B2 (en)
EP (1) EP2117801A1 (en)
CN (1) CN101547780A (en)
DE (1) DE102007001756B4 (en)
WO (1) WO2008087484A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010000798A1 (en) * 2010-01-12 2011-07-14 Ford Global Technologies, LLC, Mich. Lining part for use in inner space of passenger car to support e.g. covers, has cap-shaped circulating supporting edge provided between bearing pivot and lining part in transition region, where edge is arranged on non-visible rear part
DE102012014013B4 (en) * 2012-07-17 2022-02-24 Illinois Tool Works Inc. Method and device for producing a plastic part, in particular a plastic part for an automobile, in an injection molding process
JP7287322B2 (en) 2020-03-25 2023-06-06 トヨタ自動車株式会社 METHOD AND APPARATUS FOR MANUFACTURING FIBER REINFORCED RESIN MOLDED PRODUCTS

Citations (10)

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Publication number Priority date Publication date Assignee Title
JPH04320819A (en) * 1991-04-22 1992-11-11 Sekisui Chem Co Ltd Injection mold and manufacture for molded item
JPH05154862A (en) * 1991-12-05 1993-06-22 Honda Motor Co Ltd Molding method of hollow resin molded product
JPH05200796A (en) * 1992-01-24 1993-08-10 Honda Motor Co Ltd Method and device for manufacturing hollow resin molded product
JPH06293040A (en) * 1993-04-09 1994-10-21 Asahi Chem Ind Co Ltd Hollow injection molding method
JPH07100854A (en) * 1993-10-06 1995-04-18 Tenshiyou Denki Kogyo Kk Method for blocking gas channel of gas blowing molding method
JPH09272138A (en) * 1996-04-05 1997-10-21 Musashi Kako Kk Mold for hollow injection molding
WO1998034771A1 (en) * 1997-02-10 1998-08-13 Perstorp Ab A process in the manufacturing of a plastic product
DE19754006A1 (en) * 1997-12-05 1999-06-10 Ver Foerderung Inst Kunststoff Forming openings into hollow chambers in plastic moldings produced by gas injection
JP2000271967A (en) * 1999-03-24 2000-10-03 Honda Lock Mfg Co Ltd Mold apparatus for molding resin part
JP2005053210A (en) * 2003-07-24 2005-03-03 Tokai Kogyo Co Ltd Manufacturing process of resin product and hollow resin molding

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NL8501393A (en) * 1985-05-14 1986-12-01 Arbo Handel Ontwikkeling DEVICE FOR ENCLOSING A NUMBER OF ELECTRONIC COMPONENTS AT THE SAME TIME.
DE3913109C5 (en) 1989-04-21 2010-03-18 Ferromatik Milacron Maschinenbau Gmbh Method for injection molding of fluid-filled plastic body and device for carrying out the method

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04320819A (en) * 1991-04-22 1992-11-11 Sekisui Chem Co Ltd Injection mold and manufacture for molded item
JPH05154862A (en) * 1991-12-05 1993-06-22 Honda Motor Co Ltd Molding method of hollow resin molded product
JPH05200796A (en) * 1992-01-24 1993-08-10 Honda Motor Co Ltd Method and device for manufacturing hollow resin molded product
JPH06293040A (en) * 1993-04-09 1994-10-21 Asahi Chem Ind Co Ltd Hollow injection molding method
JPH07100854A (en) * 1993-10-06 1995-04-18 Tenshiyou Denki Kogyo Kk Method for blocking gas channel of gas blowing molding method
JPH09272138A (en) * 1996-04-05 1997-10-21 Musashi Kako Kk Mold for hollow injection molding
WO1998034771A1 (en) * 1997-02-10 1998-08-13 Perstorp Ab A process in the manufacturing of a plastic product
DE19754006A1 (en) * 1997-12-05 1999-06-10 Ver Foerderung Inst Kunststoff Forming openings into hollow chambers in plastic moldings produced by gas injection
JP2000271967A (en) * 1999-03-24 2000-10-03 Honda Lock Mfg Co Ltd Mold apparatus for molding resin part
JP2005053210A (en) * 2003-07-24 2005-03-03 Tokai Kogyo Co Ltd Manufacturing process of resin product and hollow resin molding

Also Published As

Publication number Publication date
US7998395B2 (en) 2011-08-16
EP2117801A1 (en) 2009-11-18
DE102007001756B4 (en) 2008-12-18
CN101547780A (en) 2009-09-30
US20100072680A1 (en) 2010-03-25
DE102007001756A1 (en) 2008-07-17

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