EP0099104A2 - Procédé de coulée sous pression - Google Patents

Procédé de coulée sous pression Download PDF

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Publication number
EP0099104A2
EP0099104A2 EP83106811A EP83106811A EP0099104A2 EP 0099104 A2 EP0099104 A2 EP 0099104A2 EP 83106811 A EP83106811 A EP 83106811A EP 83106811 A EP83106811 A EP 83106811A EP 0099104 A2 EP0099104 A2 EP 0099104A2
Authority
EP
European Patent Office
Prior art keywords
pressure
casting
melt
mold
gas pressure
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.)
Granted
Application number
EP83106811A
Other languages
German (de)
English (en)
Other versions
EP0099104B1 (fr
EP0099104A3 (en
Inventor
Ivan Dimov Dipl.-Ing. Nikolov
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.)
INSTITUT PO METALOSNANIE I TECHNOLOGIA NA METALITE
Institute po Metaloznanie i Technologia na Metalite
Original Assignee
INSTITUT PO METALOSNANIE I TECHNOLOGIA NA METALITE
Institute po Metaloznanie i Technologia na Metalite
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 INSTITUT PO METALOSNANIE I TECHNOLOGIA NA METALITE, Institute po Metaloznanie i Technologia na Metalite filed Critical INSTITUT PO METALOSNANIE I TECHNOLOGIA NA METALITE
Priority to AT83106811T priority Critical patent/ATE30126T1/de
Publication of EP0099104A2 publication Critical patent/EP0099104A2/fr
Publication of EP0099104A3 publication Critical patent/EP0099104A3/de
Application granted granted Critical
Publication of EP0099104B1 publication Critical patent/EP0099104B1/fr
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D18/00—Pressure casting; Vacuum casting

Definitions

  • the invention relates to a die casting process in which the melt is conveyed from a melt container to a casting mold and fills it under the effect of a pressure difference which is produced between the melting container and the casting mold, so that the melt is filled under vacuum, atmospheric during the filling of the casting mold and increased pressure.
  • a die casting method is known in which the melt present in a liquid metal container flows to the casting mold via a closed material line and fills it under the influence of a pressure difference in the melt container and in the casting mold.
  • the mold is filled at atmospheric pressure.
  • a suitable vacuum is created in the casting mold, so that one can thus control the speed of the complete filling of the mold.
  • a disadvantage of this process is that the melt solidifies under the existing vacuum or low pressure conditions. This makes it impossible to get one Control of the crystallization process in the entire volume of the casting, especially in the case of a complicated shape. This has a negative influence on the physical-mechanical properties of the casting.
  • the invention has for its object to design the die casting process of the type mentioned so that the mold filling and crystallization process can be safely controlled for all areas of the casting with minimal energy losses in order to be able to produce castings with excellent physical-mechanical properties from different materials.
  • This object is achieved on the basis of the method of the type mentioned at the outset, according to the invention, in that, after the casting mold has been filled to a certain height, an additional gas pressure is generated in one or some cavities which have not yet been filled and which is substantially greater than that currently in the casting mold existing gas pressure is, at the same time the additionally generated gas pressure is compensated for by a gas pressure generated on the other side of the casting mold.
  • the additionally generated gas pressure can be maintained in the casting mold until the melt has completely solidified, or can be varied, in particular increased, from the time the pressure is generated until the crystallization process is completed.
  • the process according to the invention has the advantage that the additional gas pressure begins to act on the melt at a point in time which is selected as a function of the shape and the material of the casting mold, where the pressure is generated within the mold.
  • the casting mold filling and the crystallization of the melt are influenced, these two processes being able to be controlled simultaneously and with a minimal expenditure of energy. This enables the production of castings with excellent physical-mechanical properties, regardless of the shape of the castings.
  • the device shown in FIG. 1 for carrying out the die casting method has a melt container 1 which is connected to a casting mold 3 via a material line 2.
  • the casting mold 3 consists of two parts, a lower half-mold 31 and an upper half-mold 32.
  • a casting cavity 4 is formed between the two half-molds 31 and 32. Additional cavities 5 are present in the upper half mold 32.
  • the melt container 1 is connected to a compressed gas source 6 via a valve 7.
  • the pressure P 1 in the compressed gas source 6 corresponds to the casting pressure.
  • the melt container 1 is provided with a pressure measuring device 8, which is connected via a converter 9 and a valve 10 to a gas container 13 with high pressure P 3 .
  • an intensifier cylinder 11 with a stepped piston which is connected on the one hand via a control throttle 12 and a pipe to the additional cavities 5 and on the other hand via a further pipe and the valve 10 to the gas container 13.
  • the casting process in this embodiment takes place as follows: after preparation of the melt, a pressure difference is generated between the melt container 1 and the casting mold 3, so that, regardless of whether there is a vacuum, atmospheric or increased pressure in the casting mold 3, the casting cavity 4 via the material line is filled. During the filling process, the casting pressure rises due to the overcoming of the frictional forces, the hydraulic height of the melt and the throttling action of the gases escaping through the ventilation openings, so that the filling takes place gradually and suddenly.
  • the casting pressure P T p changes, for example as a result of a change in the cross section of the casting.
  • the converter 9 takes effect. It opens the valve 10 so that gas from the gas container 13 is passed to the additional cavities 5 of the casting mold 3 which are not yet filled and to the booster cylinder 11, as a result of which the high pressure P 3 in the casting mold 3 . prevails.
  • the flow of melt from the melt container 1 is interrupted by the movement of the stepped piston in the booster cylinder 11 and the complete filling of the casting mold 3 with the melt is ended. After pressure shut-off, cooling and removal of the finished casting, the casting cycle is repeated.
  • the melt container consists of a cylinder 1 which is connected to the casting mold by a pouring tube.
  • the casting mold is composed of a left half mold 31 and a right half mold 32 and has a casting cavity 4 and additional cavities 5, namely risers.
  • the cylinder 1 is connected via a valve 7, a pipeline and a power cylinder 18 equipped with a pressure measuring device 8 to a pressure source 6 with a pressure P 1 .
  • the power cylinder 18 is connected to an intensifier cylinder 11, which is connected on the one hand via a pipe to the casting cavity 4 and on the other hand via a valve 14 to a gas container 13 with high pressure P 3 .
  • the pressure measuring device 8 is connected to the additional cavity 5 and the booster cylinder 11 via a converter 9 and a valve 10.
  • a control throttle 12 is seated in the connecting line between the converter 9 and the additional cavity 5.
  • pistons for motor vehicles are to be cast from an AlSi alloy which have a jacket wall thickness of 6 mm, a reinforcement ring in the lower area of the jacket, a reinforcement of 20 mm in the area of the piston pin eyes and a piston head thickness of 25 mm .
  • the two-part mold 3 is made of metal and has a composite core for the central opening and cores for the radial openings. Venting channels, a pouring tube and additional cavities 5 forming risers are also formed in the casting mold 3.
  • a gas pressure of 60 MPa is generated in the booster cylinder 11 by opening the valve 14.
  • the valve 14 is later closed and a measured amount of melt is poured into the cylinder 1.
  • a pressure is generated from the compressed gas source 6 in the power cylinder 18 and in the booster cylinder 11.
  • the piston of the power cylinder 18 conveys the melt, which fills the casting cavity 4 of the casting mold 3.
  • the casting pressure or delivery pressure P TP displayed by the pressure measuring device 8 changes. If the riser is partially filled, the casting pressure changes at point "a" in FIG. 4. After a signal from the pressure measuring device 8, the converter 9 is actuated so that the valve 10 opens.
  • the stepped piston of the booster cylinder 11 is driven, as a result of which a pressure of 300 MPa prevails in the risers forming the additional cavities 5.
  • the pressure thus produced is removed until the casting has completely crystallized.
  • the device of FIG. 5 has a container 1 filled with molten metal, which is connected to the casting mold 3 via a material line 2.
  • the casting cavity 4 is located between the upper half mold 31 and the lower half mold 32 of the casting mold 3.
  • the additional cavities 5, namely risers, are provided in the upper half mold 32.
  • the melt container 1 is connected to the pressure source 6 with a pressure P 1 via a valve 7.
  • the melt container 1 and the space of the casting mold 3 are equipped with a pressure measuring device 8, which is provided with a converter 9. Via the valve 10, the converter 9 is connected to the gas container 13 at high pressure P 3 .
  • the gas container 13 is connected via the valve 10 to the booster cylinder 11, which is connected to the lower half mold 31.
  • the connection between the piston antechamber of the booster cylinder 11 and the additional cavities 5 of the casting mold is made via the control throttle 12.
  • the space of the casting mold 3 is connected to a vacuum container 17 via a pipeline and a valve 16.
  • components of a motor vehicle suspension are cast from aluminum alloy, in a complicated thin and thick-walled version with thicknesses of 4 to 25 mm.
  • the thicker areas are concentrated in three places and are 300 to 400 mm away from the central opening, whereby a complicated ribbing with a rib height of up to 90 mm is provided.
  • the casting process takes place in a two-part metal mold, which is in a hermetically sealed chamber is arranged.
  • the separating surface of the two half molds 31 and 32 is complicated.
  • the risers are formed over the massive areas of the casting. Vent channels are incorporated in the mold itself.
  • the cavities between the individual ribs are designed as inlays, with ventilation channels being provided between them.
  • a high pressure is generated in the additional cavity 5 of the casting mold 3 and is compensated for by the step piston of the booster cylinder 11.
  • the high pressure is maintained until the solidification process has ended, while the vacuum only prevails until the mold 3 is filled. After the high pressure has been released, the casting is removed.
  • the device of FIG. 7 has a melt container 1, which is connected via the material line 2 to the casting mold 3, which is composed of a left half mold 31 and a right half mold 32 and surrounds the casting cavity 4 formed therebetween.
  • the additional cavities 5, namely the risers, are incorporated in the left half mold 31.
  • the melt container 1 is via the valve 7 to the compressed gas source 6 connected with the pressure P 1 .
  • the compressed gas source 6 is connected to the mold 3 via a valve 15.
  • a pressure measuring device 8 is attached to the melt container 1 and is provided with a converter 9 which is connected via the valve 10 to the gas container 13 with high pressure P 3 .
  • the gas container 13 and the booster cylinder 11 are connected to each other and connected to the right half mold 32.
  • the two-part mold is provided with elastic seals.
  • a deep and wide channel is worked out between the sealing ring and the casting cavity, which is connected to the casting cavity by ventilation channels. Further ventilation channels and a space for a riser are provided in the casting mold.
  • melt made of technically pure zinc is introduced, which is pressurized to 10 bar with nitrogen.
  • a pressure of 10 bar is then set in the melt container 1 - casting mold 3 system. Due to the pressure difference generated, the mold 3 is filled up to the level AA, which corresponds to point 2a in FIG. 8, so that the casting pressure changes.
  • the converter 9, which opens the valve 10, is actuated by a signal from the pressure measuring device 8. This builds up in the unfilled additional Cavity 5 of the mold 3 to a pressure of 96 bar, which is compensated for by the pressure from the booster cylinder 11.
  • the flow of melt from the melt container 1 is interrupted by the movement of the stepped piston of the booster cylinder 11.
  • the mold 3 is completely filled under high pressure. After the crystallization process has ended, the pressure in the casting mold 3 is reduced, the casting is cooled and removed.

Landscapes

  • Mechanical Engineering (AREA)
  • Engineering & Computer Science (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
  • External Artificial Organs (AREA)
  • Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)
  • Separation By Low-Temperature Treatments (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • Encapsulation Of And Coatings For Semiconductor Or Solid State Devices (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Mechanical Treatment Of Semiconductor (AREA)
  • Casting Devices For Molds (AREA)
  • Apparatus For Radiation Diagnosis (AREA)
  • Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
  • Manufacture Of Motors, Generators (AREA)
  • Manufacture, Treatment Of Glass Fibers (AREA)
  • Iron Core Of Rotating Electric Machines (AREA)
  • Superconductors And Manufacturing Methods Therefor (AREA)
  • Ceramic Products (AREA)
  • Powder Metallurgy (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Reinforced Plastic Materials (AREA)
  • Inorganic Insulating Materials (AREA)
EP83106811A 1982-07-14 1983-07-11 Procédé de coulée sous pression Expired EP0099104B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83106811T ATE30126T1 (de) 1982-07-14 1983-07-11 Druckgiessverfahren.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
BG8257405A BG34491A1 (en) 1982-07-14 1982-07-14 Method for casting under pressure
BG57405/82 1982-07-14

Publications (3)

Publication Number Publication Date
EP0099104A2 true EP0099104A2 (fr) 1984-01-25
EP0099104A3 EP0099104A3 (en) 1984-02-22
EP0099104B1 EP0099104B1 (fr) 1987-10-07

Family

ID=3911019

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83106811A Expired EP0099104B1 (fr) 1982-07-14 1983-07-11 Procédé de coulée sous pression

Country Status (17)

Country Link
EP (1) EP0099104B1 (fr)
JP (1) JPS5947062A (fr)
AT (1) ATE30126T1 (fr)
AU (1) AU558220B2 (fr)
BG (1) BG34491A1 (fr)
BR (1) BR8303740A (fr)
CS (1) CS235980B2 (fr)
DD (1) DD265994A3 (fr)
DE (1) DE3373986D1 (fr)
DK (1) DK315283A (fr)
ES (1) ES524043A0 (fr)
HU (1) HU198276B (fr)
IN (1) IN159558B (fr)
NO (1) NO161783C (fr)
PL (1) PL242987A1 (fr)
RO (1) RO87711A (fr)
SU (1) SU1389933A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0221196A1 (fr) * 1985-10-08 1987-05-13 Institut Po Metalosnanie I Technologia Na Metalite Procédé et dispositif pour la coulée sous pression
DE3618059A1 (de) * 1986-05-28 1987-12-03 Bbc Brown Boveri & Cie Niederdruck-giessverfahren und vorrichtung zu dessen herstellung
EP0585598A1 (fr) * 1992-09-01 1994-03-09 General Motors Corporation Coulée de métaux à l'aide d'un moule avec masselottes fixée dans le moule
GB2294000A (en) * 1994-10-14 1996-04-17 Honda Motor Co Ltd Thixocasting
US6321825B1 (en) * 1998-05-13 2001-11-27 Georg Fischer Disa Ag Process and apparatus for the uphill low pressure casting of metal, particularly light metal

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0629381Y2 (ja) * 1988-03-24 1994-08-10 株式会社大井製作所 車両用インサイドハンドル装置
RU2385783C1 (ru) * 2008-10-28 2010-04-10 Федеральное государственное образовательное учреждение высшего профессионального образования "Сибирский федеральный университет" Способ получения фасонных отливок алюминиево-кремниевых сплавов
KR101199061B1 (ko) 2010-06-11 2012-11-07 현대자동차주식회사 도어트림용 핸들
US8434460B2 (en) 2010-10-29 2013-05-07 Ford Global Technologies, Llc Integrally molded carbon canister

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1178979B (de) * 1961-01-26 1964-10-01 Balgarska Akademia Na Naukite Verfahren zum Giessen von Metallen und anderen Stoffen unter Druck
IT1065981B (it) * 1976-02-04 1985-03-04 Fata S P A Ora Fata Europ Grou Procedimento ed apparecchiatura per la colata in conchiglia a bassa pressione di pezzi di lega leggera
JPS54151513A (en) * 1978-04-27 1979-11-28 Leibfried Dieter Low pressure dieecasting of metal* particularly of ne metal and apparatus therefor

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0221196A1 (fr) * 1985-10-08 1987-05-13 Institut Po Metalosnanie I Technologia Na Metalite Procédé et dispositif pour la coulée sous pression
DE3618059A1 (de) * 1986-05-28 1987-12-03 Bbc Brown Boveri & Cie Niederdruck-giessverfahren und vorrichtung zu dessen herstellung
EP0585598A1 (fr) * 1992-09-01 1994-03-09 General Motors Corporation Coulée de métaux à l'aide d'un moule avec masselottes fixée dans le moule
GB2294000A (en) * 1994-10-14 1996-04-17 Honda Motor Co Ltd Thixocasting
US5787961A (en) * 1994-10-14 1998-08-04 Honda Giken Kogyo Kabushiki Kaisha Thixocasting process, for a thixocasting alloy material
GB2294000B (en) * 1994-10-14 1998-12-23 Honda Motor Co Ltd Thixocasting process and thixocasting alloy material
US6053997A (en) * 1994-10-14 2000-04-25 Honda Giken Kogyo Kabushiki Kaisha Thixocasting process of an alloy material
US6321825B1 (en) * 1998-05-13 2001-11-27 Georg Fischer Disa Ag Process and apparatus for the uphill low pressure casting of metal, particularly light metal

Also Published As

Publication number Publication date
SU1389933A1 (ru) 1988-04-23
DE3373986D1 (en) 1987-11-12
ES8405299A1 (es) 1984-06-01
RO87711A (fr) 1985-11-30
EP0099104B1 (fr) 1987-10-07
DD265994A3 (de) 1989-03-22
CS235980B2 (en) 1985-05-15
BG34491A1 (en) 1983-10-15
PL242987A1 (en) 1984-03-12
ATE30126T1 (de) 1987-10-15
NO161783C (no) 1989-09-27
RO87711B (ro) 1985-11-01
AU1669083A (en) 1984-01-19
AU558220B2 (en) 1987-01-22
EP0099104A3 (en) 1984-02-22
DK315283A (da) 1984-01-15
ES524043A0 (es) 1984-06-01
DK315283D0 (da) 1983-07-07
NO832548L (no) 1984-01-16
CS530583A2 (en) 1984-06-18
NO161783B (no) 1989-06-19
HU198276B (en) 1989-09-28
BR8303740A (pt) 1984-02-21
JPS5947062A (ja) 1984-03-16
IN159558B (fr) 1987-05-23

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