EP0858852B1 - Filter für Metallschmelzen und Giesseinrichtung - Google Patents

Filter für Metallschmelzen und Giesseinrichtung Download PDF

Info

Publication number
EP0858852B1
EP0858852B1 EP19980101932 EP98101932A EP0858852B1 EP 0858852 B1 EP0858852 B1 EP 0858852B1 EP 19980101932 EP19980101932 EP 19980101932 EP 98101932 A EP98101932 A EP 98101932A EP 0858852 B1 EP0858852 B1 EP 0858852B1
Authority
EP
European Patent Office
Prior art keywords
filter
molten metal
duct
casting apparatus
central portion
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 - Lifetime
Application number
EP19980101932
Other languages
English (en)
French (fr)
Other versions
EP0858852A1 (de
Inventor
Takanobu Suzuki
Masatoshi Shigeno
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.)
Yamaha Motor Co Ltd
Original Assignee
Yamaha Motor Co Ltd
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 Yamaha Motor Co Ltd filed Critical Yamaha Motor Co Ltd
Publication of EP0858852A1 publication Critical patent/EP0858852A1/de
Application granted granted Critical
Publication of EP0858852B1 publication Critical patent/EP0858852B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

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
    • B22D18/04—Low pressure casting, i.e. making use of pressures up to a few bars to fill the mould
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/08—Features with respect to supply of molten metal, e.g. ingates, circular gates, skim gates
    • B22C9/086—Filters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D43/00—Mechanical cleaning, e.g. skimming of molten metals
    • B22D43/001—Retaining slag during pouring molten metal
    • B22D43/004—Retaining slag during pouring molten metal by using filtering means

Definitions

  • This invention relates to a filter for removing foreign matter from a stream of molten metal. Moreover, the invention relates to a casting apparatus including such a filter.
  • the filter assembly is arranged such that a coarse filter first eliminates large foreign matters, it is disposed such a manner as to block the duct, so that the filter itself acts as a resistance to the molten metal flowing in the duct. Especially, when the central portion of the filter assembly is clogged with foreign matters, the resistance to the molten metal flow becomes very great, so that a need might happen for the replacement of the filter assembly even when the filter is not clogged as a whole.
  • the filter assembly when the filter assembly is provided at the inlet of the duct as described above, the duct must be removed from the furnace at the time of filter replacement, posing another problem of complicated filter change.
  • the object of this invention is to provide a filter for removing foreign matter from a stream of molten metal and a casting apparatus incorporating said filter capable of reducing the influence of the filter clogging on the molten metal to a minimum and of eliminating foreign matters efficiently for a long time.
  • a filter having a central portion and a peripheral portion, wherein the molten metal flow rate in the central portion is higher than in the peripheral portion.
  • a casting apparatus comprising a furnace for holding molten metal, a mould for receiving the molten metal, the mould being connected to the furnace through a duct, said molten metal being poured into the mould through said duct by using a pressure difference between the inside of the furnace and the inside of the mould, and a filter fitted inside said duct for eliminating impurities from the molten metal flowing to the mould wherein the molten metal passage rate in the central portion is set higher than in the peripheral portion therearound.
  • numeral 1 shows a low pressure casting apparatus.
  • the low pressure casting apparatus 1 is arranged such that it is composed of a furnace 3 containing a crucible 2, a mold 10 formed with a mold cavity 4 for a cast product, and a duct 6 the lower end of which is immersed close to the bottom of the crucible 2 and the upper end of which is connected to pouring gates 10a of the mold 10, and that the molten metal rises in the duct 6 against its gravity to be poured from the pouring gates 10a into the mold cavity 4 when compressed air or inert gas is introduced into the furnace 3 so as to apply pressure to the molten metal in the crucible 2.
  • the mold 10 is composed of a mold body 11 formed with a mold cavity 4 and made up of four split dies dividable through backward and forward and rightward and leftward sliding movement, and an upper mold 12 and a lower mold 12 defining the upper and lower ends of the mold cavity 4; and is held at a given pressure by upper and lower mold die bases 15, 14.
  • the pouring gate 10a though only one gate is shown in Fig. 1, the lower mold 13 is formed with a plurality of pouring gates, the duct 6 having an enlarged diameter in the shape of a funnel at its top 6a so as to cover all the pouring gates 10a.
  • the mold 10 as shown in Fig. 2, is arranged in such a manner as to be separated from the duct 6 together with the upper and lower mold die bases 15, 14.
  • a filter 20 is held between the lower end of the mold 10 or more specifically the bottom of the lower mold 13 and the top of the duct 6.
  • Figs. 4(a), (b) are a top view of the filter 20 and a sectional view taken along line A-A.
  • the filter 20 is made of a wire net in the shape of a flat hull bottom, formed at its top end with a flanged section 21 extending radially outwardly, the flanged section having four fitting tongues 22 extending outwardly at the front and rear, and the sides, respectively.
  • an opening 20a In the central portion of the bottom of the wire net constituting an filter surface of the filter 20, is formed an opening 20a whose sectional area is at least larger than the total sectional areas of the pouring gates 10a of the mold 10.
  • the filter 20 described above, as shown in Fig. 3, is placed on the duct 6 so as to be engaged at its flanged section with the top end of the duct, fixed at the tongues 22 to the duct 6 with appropriate fixing members such as bolts, and then held between the mold 10 and the duct 6, with the mold 10 mounted to the top of the duct 6.
  • molten metal in the crucible 2 rises in the duct 6 against its gravity, as shown in Fig. 1.
  • the molten metal flow goes up at an appropriately adjusted velocity through pressure applied to the furnace 3 depending on the shape of the mold cavity 4 of the mold 10 or the material of the molten metal.
  • the flow velocity is basically zero on the wall surface 6b of the duct 6, it is highest at the duct center and decreases as the flow approaches the wall surface 6b radially outwardly from the duct center. Therefore, the molten metal flows in the duct while spreading radially outwardly as shown by arrows in Fig.
  • Fig. 5 is a diagram showing the measurement of the deposition of foreign matters (so-called slag) to the quantity of filtered molten metal (unit weight ⁇ number of shots).
  • the diagram shows that the deposition of foreign matters increases in proportion to the quantity of the filtered molten metal, and accordingly the filter 20 has adequate durability in collecting foreign matters.
  • the filter is arranged such that an opening 20a is provided in the central portion and a wire net section is located only in the outer portion where foreign matters accumulate, allowing the resistance of the clogged foreign matters to the molten metal flow to be reduced to a smallest possible level, which prevents poor run of the molten metal due to decreased flow velocity caused by filter clogging. Further, this allows changes in the filter resistance over time to the molten metal to be restricted to a minimum, so that difficulties such as development of burrs caused by changes in flow velocity can be controlled to a lowest level even for a long-term use in the same casting condition, which effects stability in the quality of products.
  • the filter 20 is arranged such that it is provided with a flanged section 21 which can be held between the duct 6 and the lower mold 13. Therefore, as shown in Fig. 2, the filter can be removed easily if the mold 10 is simply raised upwardly, thereby effecting easy replacement of the filter.
  • the filter 20 is formed in the shape of a flat hull bottom, so that the area of the peripheral filter section can be enlarged.
  • an opening 20a is formed in the central portion which has no influence on the filtering effect of the filter 20, so that the filter 20 will not change its original form for a long-term use because of its small resistance to the molten metal flow.
  • the filter 20 may be formed of various materials depending on the casting conditions such as material and temperature of the molten metal.
  • it can be formed of, but not limited to, a SUS 304-plated wire net with a surface oxidized in an atmosphere at 500°C, preferably a zinc-plated wire net oxidized in an atmosphere at 500 °C, or a ceramic-coated wire net etc.
  • the filter 20 may be made of materials other than the wire net, for example, but not limited to, meshed materials such as expanded metal and punching metal, or ceramic filters.
  • the molten metal passage rate of the filter 20 at the peripheral portion may also be determined as required depending on the casting conditions such as material and temperature of the molten metal.
  • the filter 20 is of a flat hull bottom shape in this embodiment, but may be formed into any appropriate shape as long as it has an opening in the central portion, for example, the shape of a flat plate.
  • the size of the opening of the filter 20 is preferably over 35% of the minimum sectional area of the flow passage of the duct, but not limited to that, and may be determined at will within a range over which passage of the foreign matters is prevented.
  • the filter 20 is disposed between the duct 6 and the mold 10 (lower mold 13) in this embodiment, but may be disposed at any appropriate position if placed within the duct 6, preferably above the original level of the molten metal in the crucible 2, in which case, foreign matters can be eliminated reliably even when they are initially deposited on the inside wall of the duct.
  • a low pressure casting apparatus has been described as a way of example in this embodiment, but the type of the casting apparatus is not limited to that, and any type of casting apparatus with a duct through which molten metal is supplied to the mold cavity, can be employed, for example, but not limited to, casting apparatuses operated by the differential pressure casting method or the Cosworth method with a duct of an electromagnetic pump type.
  • the filter and the casting apparatus are separated from each other, but arrangement is not limited to this embodiment, and if no filter replacement is necessary or the clogged foreign matters can be removed from the filter by washing, the filter may be incorporated into the casting apparatus, for example, into the duct or the mold.
  • the filter 20 is formed with an opening in its central portion, but as long as the molten metal passage rate of the filter 20 at the central portion which has no influence on the filtering effect, is set higher than that at the peripheral portion therearound, the central portion of the filter may be formed as, for example, but not limited to, a coarse wire net having no influence on the filtering effect. This netted arrangement will effects higher rigidity of the filter itself.
  • a duct 6 with enlarged upper end diameter has been described as a way of example in this embodiment, but the shape of the duct 6 is not limited to that, and this invention can be also applied to a straight pipe duct.
  • the filter is fitted inside a duct, for eliminating impurities from molten metal flowing into a mold, in a casting apparatus having a furnace holding molten metal and the mold receiving the molten metal connected thereto through the duct forming a flow passage of the molten metal, said molten metal being poured into the mold through said duct by using pressure difference between the insides of said furnace and said mold, wherein the molten metal passage rate in the central portion is set higher than that in the peripheral portion therearound.
  • the resistance of the filter to the molten metal flow in the duct can be reduced to a smallest possible level, and changes in the filter resistance over time to the molten metal flow due to clogging can also be restricted to a minimum, so that the filter can be used for a long time without decreased filtering efficiency.
  • the casting apparatus has a furnace holding molten metal and a mold receiving the molten metal connected thereto through a duct.
  • the molten metal is poured into the mold through said duct by using pressure difference between the insides of said furnace and said mold.
  • Inside said duct there is provided a filter whose molten metal passage rate is higher in the central portion than in the peripheral portion therearound, and impurities are eliminated from the molten metal flowing from the furnace into the mold by said filter.
  • the resistance of the filter to the molten metal flow in the duct can be reduced to a smallest possible level, and changes in the filter resistance over time to the molten metal flow due to clogging can also be restricted to a minimum, so that the filter can be used for a long time without decreased filtering efficiency, which allows the frequency of filter replacement to be reduced to a minimum, thereby effecting increased manufacturing efficiency.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Claims (9)

  1. Filter (20) zum Entfernen von Fremdstoffen aus einem flußgeschmolzenen Metall, wobei der Filter (20) einen Mittelabschnitt und einen Umfangsabschnitt aufweist, wobei die Strömungsgeschwindigkeit des geschmolzenen Metalles in dem Mittelabschnitt höher ist als in dem Umfangsabschnitt.
  2. Filter nach Anspruch 1, dadurch gekennzeichnet, daß der Mittelabschnitt eine Öffnung (20a) ist.
  3. Filter nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß der Filter einen Boden in der Form eines flachen Schalenbodens aufweist, daß eine Öffnung in der Mitte des Bodens ausgebildet ist.
  4. Filter nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß der Filter (20) mit einem Flanschabschnitt (22) versehen ist, der vorgesehen ist, in Eingriff zu sein mit dem oberen Ende eines Kanales.
  5. Gießvorrichtung mit:
    einem Ofen (3) zur Aufnahme geschmolzenen Metalls,
    einer Gießform (10) zur Aufnahme des geschmolzenen Metalls, wobei die Gießform (10) mit dem Ofen (3) über einen Kanal (6) verbunden ist,
    wobei das geschmolzene Metall in die Gießform (10) durch den Kanal (6) unter Verwendung einer Druckdifferenz zwischen dem Inneren des Ofens (3) und dem Inneren der Gießform (10) eingegossen wird, und
    einem Filter (20) eingesetzt in den Kanal zum Beseitigen von Verunreinigungen von dem geschmolzenen Metall, das in die Gießform fließt, wobei die Durchgangsgeschwindigkeit des geschmolzenen Metalls in dem Mittelabschnitt höher festgelegt ist als in dem diesen umgebenden Umfangsabschnitt.
  6. Gießvorrichtung nach Anspruch 5, dadurch gekennzeichnet, daß die Fläche des Mittelabschnittes mit einer höheren Durchgangsgeschwindigkeit des geschmolzenen Metalles größer ist als die Gesamtquerschnitte der Eingießöffnungen (10a) der Gießform (10).
  7. Gießvorrichtung nach Anspruch 5 oder 6, dadurch gekennzeichnet, daß der Mittelabschnitt mit einer höheren Durchgangsgeschwindigkeit für das geschmolzene Metall eine Öffnung (20a) ist.
  8. Gießvorrichtung nach einem der Ansprüche 5 bis 7, dadurch gekennzeichnet, daß der Filter (20) einen Boden in Form eines flachen Schalenbodens aufweist und mit einer Öffnung in der Mitte des Bodens versehen ist.
  9. Gießvorrichtung nach einem der Ansprüche 5 bis 8, dadurch gekennzeichnet, daß der Filter (20) mit einem Flanschabschnitt (22) versehen ist, der mit dem oberen Ende des Kanales (6) in Eingriff bringbar ist, wobei der Filter mit dem Flanschabschnitt (22) gehalten ist zwischen dem oberen Ende des Kanales (6) und dem Boden der Gießform (10).
EP19980101932 1997-02-07 1998-02-04 Filter für Metallschmelzen und Giesseinrichtung Expired - Lifetime EP0858852B1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP02503397A JP3614598B2 (ja) 1997-02-07 1997-02-07 鋳造装置用フィルタ及び鋳造装置
JP25033/97 1997-02-07
JP2503397 1997-02-07

Publications (2)

Publication Number Publication Date
EP0858852A1 EP0858852A1 (de) 1998-08-19
EP0858852B1 true EP0858852B1 (de) 2001-09-19

Family

ID=12154608

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19980101932 Expired - Lifetime EP0858852B1 (de) 1997-02-07 1998-02-04 Filter für Metallschmelzen und Giesseinrichtung

Country Status (3)

Country Link
EP (1) EP0858852B1 (de)
JP (1) JP3614598B2 (de)
DE (1) DE69801690T2 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008055490A2 (de) * 2006-11-08 2008-05-15 Aug. Gundlach Kg Vertikalgussvorrichtung zur herstellung von formteilen

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19843285A1 (de) * 1998-09-22 2000-03-23 Georg Fischer Disa Ag Vorrichtung zum steigenden Niederdruck-Gießen von Metallen, insbesondere Leichtmetallen
DE19859032C2 (de) * 1998-12-21 2001-09-20 Ks Aluminium Technologie Ag Gießfilter zum Gießen von Metalllegierung
DE19859031C5 (de) * 1998-12-21 2012-08-02 ASTI Gießereigeräte GmbH Anordnung eines Gießfilters, Gießfilter und dessen Verwendung
CN103658599B (zh) * 2013-11-15 2015-10-28 中北大学 一种适用于电磁泵低压铸造充型工艺的设计方法
CN106735088B (zh) * 2017-01-15 2020-06-16 丹阳荣嘉精密机械有限公司 低压成型专用铸造模具
KR102132535B1 (ko) * 2018-10-04 2020-07-09 정상길 차량용 알루미늄휠 성형장치

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1867524U (de) * 1962-12-06 1963-02-21 Alcan Aluminiumwerke Steigrohr mit sieb fuer das niederdruckgiessverfahren fuer leichtmetalle.
JPS4873328A (de) * 1971-12-27 1973-10-03
DE3244079A1 (de) * 1982-11-29 1984-06-14 BBC Aktiengesellschaft Brown, Boveri & Cie., Baden, Aargau Sieb zur zurueckhaltung von oxydhaeuten beim vergiessen von aluminium und seinen legierungen
JPS61199566A (ja) * 1985-02-28 1986-09-04 Daihatsu Motor Co Ltd 低圧鋳造用ストーク
JPH02241656A (ja) * 1989-03-14 1990-09-26 Hitachi Metals Ltd 鋳造装置
JPH07284904A (ja) * 1994-04-21 1995-10-31 Hitachi Metals Ltd 差圧鋳造用ストーク

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008055490A2 (de) * 2006-11-08 2008-05-15 Aug. Gundlach Kg Vertikalgussvorrichtung zur herstellung von formteilen
WO2008055490A3 (de) * 2006-11-08 2008-07-17 Aug Gundlach Kg Vertikalgussvorrichtung zur herstellung von formteilen

Also Published As

Publication number Publication date
JPH10216901A (ja) 1998-08-18
EP0858852A1 (de) 1998-08-19
DE69801690T2 (de) 2002-04-18
DE69801690D1 (de) 2001-10-25
JP3614598B2 (ja) 2005-01-26

Similar Documents

Publication Publication Date Title
US4081371A (en) Filtering of molten metal
US5741422A (en) Molten metal filter cartridge
US4125146A (en) Continuous casting processes and apparatus
EP0165025B1 (de) Keramisches Vielfach-Filter für geschmolzenes Metall
US5676731A (en) Method for filtering molten metal
JP2001513148A (ja) 溶融金属用のモジュール方式濾過器システム
EP0858852B1 (de) Filter für Metallschmelzen und Giesseinrichtung
EP0927568A1 (de) Keramische Filter, Filtereinrichtungen und Verfahren zum Filtrieren von Metallschmelzen
CA1130980A (en) Method for the filtration of molten metal
US5139238A (en) Ceramic filters in refractory bodies for cleaning molten metal
EP0726115A1 (de) Giesswanne
CN211052453U (zh) 一种用于合金钢铸件的浇铸装置
JPH11320083A (ja) 溶解保持炉
AU628606B2 (en) Filters
EP0668804B1 (de) Filtration von geschmolzenen metallen
AU8922001A (en) Device for filtering and adding grain refining agent to metal melts
EP0312549B1 (de) Feuerfestes keramisches bauteil
JPS63224854A (ja) 圧力鋳造機用セラミツクフイルタ
SU1720782A1 (ru) Литникова система дл сифонной заливки керамических форм
US6224818B1 (en) System and method for purifying molten metal
US20210023614A1 (en) Casting filter
JPS60221158A (ja) 連続鋳造設備
CN221715587U (zh) 一种过滤式浇口杯
RU1836613C (ru) Индукционна канальна печь
JPH089158Y2 (ja) 金属溶湯フィルターカートリッジ

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB IT

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 19990212

AKX Designation fees paid

Free format text: DE FR GB IT

RBV Designated contracting states (corrected)

Designated state(s): DE FR GB IT

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

17Q First examination report despatched

Effective date: 20001116

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT

REF Corresponds to:

Ref document number: 69801690

Country of ref document: DE

Date of ref document: 20011025

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20110218

Year of fee payment: 14

Ref country code: FR

Payment date: 20110302

Year of fee payment: 14

Ref country code: IT

Payment date: 20110221

Year of fee payment: 14

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20110217

Year of fee payment: 14

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20120204

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20121031

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20120204

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 69801690

Country of ref document: DE

Effective date: 20120901

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20120204

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20120229

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20120901