EP0099104B1 - Druckgiessverfahren - Google Patents

Druckgiessverfahren Download PDF

Info

Publication number
EP0099104B1
EP0099104B1 EP83106811A EP83106811A EP0099104B1 EP 0099104 B1 EP0099104 B1 EP 0099104B1 EP 83106811 A EP83106811 A EP 83106811A EP 83106811 A EP83106811 A EP 83106811A EP 0099104 B1 EP0099104 B1 EP 0099104B1
Authority
EP
European Patent Office
Prior art keywords
pressure
casting
melt
casting mould
mold
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.)
Expired
Application number
EP83106811A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0099104A3 (en
EP0099104A2 (de
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
Original Assignee
INSTITUT PO METALOSNANIE 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 filed Critical INSTITUT PO METALOSNANIE I TECHNOLOGIA NA METALITE
Priority to AT83106811T priority Critical patent/ATE30126T1/de
Publication of EP0099104A2 publication Critical patent/EP0099104A2/de
Publication of EP0099104A3 publication Critical patent/EP0099104A3/de
Application granted granted Critical
Publication of EP0099104B1 publication Critical patent/EP0099104B1/de
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 method according to the preamble of claim 1.
  • the invention relates in particular to measures for increasing the physical-mechanical properties of the workpiece to be produced by a die casting method by pressing the material filling the mold.
  • EP-A-0 005 239 discloses a die-casting method and a device for die-casting metals, in particular non-ferrous metals, in which the essential steps are the evacuation of the recesses in the casting tool that receive the melt, the subsequent introduction of the molten metal into the casting mold and the like Applying a pressure to the molten metal in the casting tool via a melt-free excess of melt and, if appropriate, also additionally via the pouring system itself.
  • the application of the pressure by means of an excess of melt away from the casting can take place by means of a hollow part which can be brought into engagement with the overflow channel of the casting tool.
  • the known method or the known device has the disadvantage that the holding pressure is kept constant during the cooling of the casting and thus it is not possible to control the crystallization process in the entire volume of the casting, particularly in the case of a complicated shape. This has a negative impact on the physical-mechanical properties of the casting.
  • the object on which the invention is based is therefore to design the method according to the type mentioned at the outset in such a way that the mold filling and crystallization process can be reliably controlled with it in order to produce castings with better properties.
  • the process according to the invention has the advantage that a residual space of the casting mold is exposed to an increased additional gas pressure as a casting pressure that is remote from the casting and this increased additional gas pressure is compensated for by a variable back pressure on this side of the pouring opening as a casting-side printing pressure until the casting mold is completely filled.
  • the device shown in FIG. 1 for carrying out the die casting process has a melt container 1 which is connected to a casting mold 3 via a material line 2.
  • the casting mold 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 .
  • 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, an atmospheric pressure or an increased pressure in the casting mold 3, the casting cavity 4 is filled via the material line. During the filling process, the casting pressure increases due to the overcoming of the frictional forces, the hydraulic height of the melt and the throttling effect of the gases escaping through the ventilation openings, so that the filling takes place gradually.
  • the casting pressure P TP P 2 changes , for example as a result of a change in the cross section of the casting.
  • the converter 9 takes effect on a signal from the pressure measuring device 8 for the casting pressure. 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 prevails in the casting mold 3.
  • 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 the 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 3 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 AISi 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 bar is generated in the smaller diameter part of the booster cylinder 11 from the container 13 by opening the valve 14. After reaching the value of 60 bar, the valve 14 is closed.
  • the size of this pressure is selected in advance depending on the workpiece to be cast.
  • the piston in the cylinder 11 which has variable cross sections, comes into the position shown in the upper part of FIG. 3.
  • a volume of the melt is brought into the casting mold, whereupon when the valve 7 is opened from the container 6 in the power cylinder 18 and in the booster cylinder 11 on the right side of the piston, the pressure P i is generated, which according to the diagram in FIG changes, the filling of the mold begins.
  • P 1 P TP
  • the size “a ” FIG.
  • the converter 9 is activated according to the signal from the pressure measuring device M brought into effect and the valve 10.
  • a pressure of 300 bar now arises, corresponding to the difference in the piston cross sections in the cylinder 11.
  • This pressure is countered by a counterpressure on the side of the casting opening is generated by the piston in the material cylinder 1, which is selected according to the desired pressure difference in relation to the piston power cylinder 18.
  • the final filling of the casting mold takes place under the high pressure mentioned, by counteracting this pressure in the manner mentioned.
  • 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 lower half mold 31 and the upper 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 with 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 an aluminum alloy, in a complicated thin and thick-walled design 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 arranged in a hermetically sealed chamber.
  • the risers are formed over the massive areas of the casting. Vent channels are incorporated into the mold itself.
  • a vacuum of 0.1 to 0.2 MPa is generated in the chamber with the casting mold 3 by opening the valve 16 via the vacuum source 17.
  • the pressure difference between the melt container 1 and the casting mold 3 begins to fill the casting cavity 4.
  • the melt begins to fill the ventilation channels at the parting surface of the mold, the casting pressure changes.
  • the converter 9 is actuated, which opens the valve 10.
  • a high pressure is generated in the additional cavity 5 of the casting mold 3, which pressure is compensated for by the pressure of 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.
  • the casting is removed.
  • Fig. 6 shows the associated course of the casting pressure.
  • the melt container 1 is connected via the valve 7 to the compressed gas source 6 with the pressure P 1 .
  • the compressed gas source 6 is connected to the mold 3 via a valve 15 so that the entire system is under the same and increased pressure.
  • the casting process therefore begins with a counter pressure.
  • the melt is initially pressurized with nitrogen under pressure from the source 6 when the valve 7 is open and when the valve 15 is closed.
  • the pressure difference between the cavity of the mold and the melt container 1 is realized for the original filling by gas discharge from the cavity of the mold.
  • 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 piston antechamber of the booster cylinder 11 is connected to the additional cavities 5.
  • 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 with nitrogen under a pressure of 10 bar.
  • a pressure of 10 bar is then set in the melt container 1 and casting mold 3 system. Due to the pressure difference generated, the mold 3 is filled up to level A-A, which corresponds to point a 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.
  • a pressure of 96 bar builds up in the non-filled additional cavity 5 of the casting mold 3, which pressure 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 step piston of the booster cylinder 11 after the mold 3 has been 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)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)
  • Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)
  • External Artificial Organs (AREA)
  • Separation By Low-Temperature Treatments (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • Mechanical Treatment Of Semiconductor (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Encapsulation Of And Coatings For Semiconductor Or Solid State Devices (AREA)
  • Apparatus For Radiation Diagnosis (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Ceramic Products (AREA)
  • Superconductors And Manufacturing Methods Therefor (AREA)
  • Powder Metallurgy (AREA)
  • Reinforced Plastic Materials (AREA)
  • Inorganic Insulating Materials (AREA)
  • Iron Core Of Rotating Electric Machines (AREA)
  • Manufacture Of Motors, Generators (AREA)
  • Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
  • Manufacture, Treatment Of Glass Fibers (AREA)
  • Casting Devices For Molds (AREA)
EP83106811A 1982-07-14 1983-07-11 Druckgiessverfahren Expired EP0099104B1 (de)

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
BG57405/82 1982-07-14
BG8257405A BG34491A1 (en) 1982-07-14 1982-07-14 Method for casting under pressure

Publications (3)

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

Family

ID=3911019

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83106811A Expired EP0099104B1 (de) 1982-07-14 1983-07-11 Druckgiessverfahren

Country Status (17)

Country Link
EP (1) EP0099104B1 (no)
JP (1) JPS5947062A (no)
AT (1) ATE30126T1 (no)
AU (1) AU558220B2 (no)
BG (1) BG34491A1 (no)
BR (1) BR8303740A (no)
CS (1) CS235980B2 (no)
DD (1) DD265994A3 (no)
DE (1) DE3373986D1 (no)
DK (1) DK315283A (no)
ES (1) ES8405299A1 (no)
HU (1) HU198276B (no)
IN (1) IN159558B (no)
NO (1) NO161783C (no)
PL (1) PL242987A1 (no)
RO (1) RO87711A (no)
SU (1) SU1389933A1 (no)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8434460B2 (en) 2010-10-29 2013-05-07 Ford Global Technologies, Llc Integrally molded carbon canister

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES8608970A1 (es) * 1985-10-08 1986-09-01 Inst Po Metalloznanie I Tekno Metodo y aparato para moldeado bajo presion
DE3618059A1 (de) * 1986-05-28 1987-12-03 Bbc Brown Boveri & Cie Niederdruck-giessverfahren und vorrichtung zu dessen herstellung
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
US5271451A (en) * 1992-09-01 1993-12-21 General Motors Corporation Metal casting using a mold having attached risers
US5787961A (en) * 1994-10-14 1998-08-04 Honda Giken Kogyo Kabushiki Kaisha Thixocasting process, for a thixocasting alloy material
DE19821419A1 (de) * 1998-05-13 1999-11-18 Georg Fischer Disa Ag Verfahren zum steigenden Niederdruck-Gießen von Metall, insbesondere Leichtmetall
KR101199061B1 (ko) 2010-06-11 2012-11-07 현대자동차주식회사 도어트림용 핸들

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 (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8434460B2 (en) 2010-10-29 2013-05-07 Ford Global Technologies, Llc Integrally molded carbon canister

Also Published As

Publication number Publication date
DE3373986D1 (en) 1987-11-12
RO87711B (ro) 1985-11-01
EP0099104A3 (en) 1984-02-22
ATE30126T1 (de) 1987-10-15
NO161783C (no) 1989-09-27
JPS5947062A (ja) 1984-03-16
HU198276B (en) 1989-09-28
EP0099104A2 (de) 1984-01-25
AU558220B2 (en) 1987-01-22
ES524043A0 (es) 1984-06-01
RO87711A (ro) 1985-11-30
ES8405299A1 (es) 1984-06-01
BG34491A1 (en) 1983-10-15
DK315283A (da) 1984-01-15
IN159558B (no) 1987-05-23
AU1669083A (en) 1984-01-19
NO832548L (no) 1984-01-16
BR8303740A (pt) 1984-02-21
CS530583A2 (en) 1984-06-18
PL242987A1 (en) 1984-03-12
DD265994A3 (de) 1989-03-22
CS235980B2 (en) 1985-05-15
NO161783B (no) 1989-06-19
SU1389933A1 (ru) 1988-04-23
DK315283D0 (da) 1983-07-07

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