EP0086321B1 - Verfahren zum Entgraten von aus körnigem Material gefertigten Sandkernen - Google Patents
Verfahren zum Entgraten von aus körnigem Material gefertigten Sandkernen Download PDFInfo
- Publication number
- EP0086321B1 EP0086321B1 EP83100035A EP83100035A EP0086321B1 EP 0086321 B1 EP0086321 B1 EP 0086321B1 EP 83100035 A EP83100035 A EP 83100035A EP 83100035 A EP83100035 A EP 83100035A EP 0086321 B1 EP0086321 B1 EP 0086321B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- bodies
- medium
- grinding
- sand cores
- rigid foam
- 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
Links
- 238000000034 method Methods 0.000 title claims abstract description 24
- 239000000463 material Substances 0.000 title description 2
- 239000006260 foam Substances 0.000 claims abstract description 16
- 239000008187 granular material Substances 0.000 claims abstract description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 10
- 229910052782 aluminium Inorganic materials 0.000 claims description 10
- 238000004513 sizing Methods 0.000 claims description 10
- -1 polypropylene Polymers 0.000 claims description 8
- 239000004743 Polypropylene Substances 0.000 claims description 6
- 239000011230 binding agent Substances 0.000 claims description 6
- 229920001155 polypropylene Polymers 0.000 claims description 6
- 239000000428 dust Substances 0.000 claims description 5
- 238000005299 abrasion Methods 0.000 claims description 3
- 239000007788 liquid Substances 0.000 claims description 2
- 239000004411 aluminium Substances 0.000 claims 3
- 239000000126 substance Substances 0.000 claims 3
- 239000005995 Aluminium silicate Substances 0.000 claims 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims 1
- 235000012211 aluminium silicate Nutrition 0.000 claims 1
- PZZYQPZGQPZBDN-UHFFFAOYSA-N aluminium silicate Chemical compound O=[Al]O[Si](=O)O[Al]=O PZZYQPZGQPZBDN-UHFFFAOYSA-N 0.000 claims 1
- 229910000323 aluminium silicate Inorganic materials 0.000 claims 1
- 239000010439 graphite Substances 0.000 claims 1
- 229910002804 graphite Inorganic materials 0.000 claims 1
- 235000011837 pasties Nutrition 0.000 claims 1
- 239000000454 talc Substances 0.000 claims 1
- 235000012222 talc Nutrition 0.000 claims 1
- 229910052623 talc Inorganic materials 0.000 claims 1
- 239000011248 coating agent Substances 0.000 abstract description 10
- 238000000576 coating method Methods 0.000 abstract description 9
- 238000000465 moulding Methods 0.000 abstract 2
- 238000005266 casting Methods 0.000 abstract 1
- 239000002344 surface layer Substances 0.000 abstract 1
- 239000003795 chemical substances by application Substances 0.000 description 5
- 239000000843 powder Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000007921 spray Substances 0.000 description 3
- 239000011148 porous material Substances 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- SXQXMCWCWVCFPC-UHFFFAOYSA-N aluminum;potassium;dioxido(oxo)silane Chemical compound [Al+3].[K+].[O-][Si]([O-])=O.[O-][Si]([O-])=O SXQXMCWCWVCFPC-UHFFFAOYSA-N 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000010433 feldspar Substances 0.000 description 1
- 210000004905 finger nail Anatomy 0.000 description 1
- 238000007373 indentation Methods 0.000 description 1
- 239000010445 mica Substances 0.000 description 1
- 229910052618 mica group Inorganic materials 0.000 description 1
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 1
- 238000011017 operating method Methods 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 229910052573 porcelain Inorganic materials 0.000 description 1
- 238000009991 scouring Methods 0.000 description 1
- 239000008400 supply water Substances 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/18—Finishing
Definitions
- the invention relates to a method for deburring sand cores made of granular material, in which the sand cores are freed of their orat by an abrasion process under the action of an abrasive medium.
- DE-A-2 731 802 It is known from DE-A-2 731 802 to deburr sand cores consisting of core sand and core binders, in particular for foundry purposes, in a drum container containing granular scouring material. As is known, the deburred sand cores then receive a size coating by immersing them in a corresponding suspension. After the dipped sand cores have dried, the coating consisting of the size remains on the surface, as a result of which the large pores of the sand cores are closed.
- the object of the invention is to provide a method of the type required, by means of which such molded parts can be deburred by machine at short notice and at the same time obtain such a size coating with no drying times.
- the cores are accordingly supplied at one point of the ring vibrator and discharged at another, preferably using a discharge sieve which allows the abrasive body medium to be fed back into the vibrator.
- the sand cores are deburred by the abrasive body medium.
- the abrasive medium containing the sizing agent gives them a uniform sizing coating at all points, which leads to the desired surface effect of the sand cores.
- Processing is preferably carried out with a large vibration amplitude.
- the rigid foam bodies are designed in such a way that slight indentation is possible with a fingernail.
- the abrasive body medium is through continuously metered addition of liquid, for. B. water, to keep at the dust limit and contains, in addition to the approximately 50% proportion of rigid foam bodies, about 15% aluminum pencils, conical grinding wheels and sizing powder.
- the sand cores get an optimal coating with sizing powder if the sizing agent content is about 10% of the volume of the grinding media.
- Particularly good embedding of the sand cores in the ring vibrator and optimal deburring are achieved if the hard foam bodies are designed as cylindrical rods and have a size comparable to that of the abrasive bodies and the size of the aluminum pins is only a fraction of the same.
- the cylindrical rods have a diameter of approximately 8 mm with a total length of approximately 16-20 mm.
- the end faces should preferably run obliquely to the longitudinal axis of the cylindrical rods.
- the conical grinding wheels they are those with a base diameter of approx. 12 mm.
- the aluminum pins on the other hand, have a diameter of 2 mm and are approx. 6 mm long.
- the device for carrying out the method preferably consists in that a ring vibrator is assigned to the edge of the ring channel a water spray device which takes effect when dust is formed and has nozzles directed towards the ring channel interior.
- the nozzles are arranged in a uniform distribution, so that the abrasive body medium receives an equal degree of moisture over the entire length of the ring channel near the dust limit.
- a ring vibrator designated as a whole by 1.
- This has a resiliently supported against a base frame 2, lying on a horizontal plane annular groove 3.
- vibrations are transmitted to the annular groove 3, which cause the abrasive medium contained therein to circulate on a helical path.
- a discharge channel 6, formed by container side walls 4, 5, extends in a secant-like orientation to the ring channel 3.
- a discharge and separation device is accommodated in the latter.
- the same has a removable, combined sieve separating box, the separating sieve 7 in the discharge position illustrated in FIG.
- a water spray device 9 is assigned to the edge of the channel 3. Specifically, this has a tube 11, which is carried by means of holding brackets 10 and is adapted to the course of the ring gutter and is equipped with nozzles 12 directed towards the interior of the gutter.
- the pipe 11 is connected to a water pipe, not shown.
- the abrasive body medium located in the ring groove 3 is composed of approx. 50% rigid polypropylene foam bodies 13, approx. 25% conical abrasive bodies 14, approx. 15% aluminum pins 15 and approx. 10% size powder.
- the polypropylene rigid foam body 13 are cylindrical in shape with a diameter x of approximately 8 mm. Their length y is approximately 16-20 mm.
- the end faces 16 and 17 extend obliquely to the longitudinal axis of these cylindrical rods at an angle alpha of approximately 30 ° such that the end faces 16, 17 are arranged parallel to one another.
- the base diameter z is approximately 12 mm.
- the cone tip is slightly flattened, so that there is a total height h of the conical grinding wheels of approx. 13 mm.
- the grinding bodies can form a fillet 18.
- the aluminum pins 15 are also cylindrical. Their diameter u is 2 mm and their length v is approximately 6 mm.
- the sizing agent is added. It preferably consists of a ground feldspar or mica, ie a potassium aluminum silicate, to which about 10% of powdered stearate has been added.
- the water spray device 9 receives the impulse to supply water to the container contents via the nozzles 12 until the corresponding degree of moisture at the dust limit is reached.
- the sand cores 19 do not damage one another because of the cushion formed by the polypropylene rigid foam bodies 13.
- the sand cores 19 at the same time receive a size coating 20 consisting of sizing agent, which closes the pores of the sand core 19 and gives it a smooth surface.
- the contents of the container reach the separating sieve 8 via the wall 8.
- the sand cores 19 are discharged while the abrasive body medium plus sizing agent (insofar as it gets onto the sieve) falls through the separating sieve 7 and is thus fed back into the interior of the annular trough becomes.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Polishing Bodies And Polishing Tools (AREA)
- Casting Devices For Molds (AREA)
- Mold Materials And Core Materials (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
- Formation Of Various Coating Films On Cathode Ray Tubes And Lamps (AREA)
- Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT83100035T ATE13985T1 (de) | 1982-01-18 | 1983-01-04 | Verfahren zum entgraten von aus koernigem material gefertigten sandkernen. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19823201284 DE3201284A1 (de) | 1982-01-18 | 1982-01-18 | Verfahren zum entgraten und schlichteueberziehen von geschossenen giesskernen |
DE3201284 | 1982-01-18 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0086321A1 EP0086321A1 (de) | 1983-08-24 |
EP0086321B1 true EP0086321B1 (de) | 1985-06-26 |
Family
ID=6153269
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP83100035A Expired EP0086321B1 (de) | 1982-01-18 | 1983-01-04 | Verfahren zum Entgraten von aus körnigem Material gefertigten Sandkernen |
Country Status (6)
Country | Link |
---|---|
US (1) | US4560586A (ja) |
EP (1) | EP0086321B1 (ja) |
JP (1) | JPS58209444A (ja) |
AT (1) | ATE13985T1 (ja) |
DE (2) | DE3201284A1 (ja) |
ES (1) | ES519074A0 (ja) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4005824C1 (en) * | 1990-02-23 | 1991-03-07 | Theodor Heimeier Metallwerk Kg, 4782 Erwitte, De | Method of deburring foundry cores - has cores placed in ring vibrator and grinding bodies added to these |
DE4019433C1 (en) * | 1990-06-19 | 1991-08-29 | Theodor Heimeier Metallwerk Kg, 4782 Erwitte, De | Removal of flash and application of wash coating to foundry cores - comprising circulating cores in ring vibrator to which grinding medium contg. two types of grinding body is added |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3322567C2 (de) * | 1983-06-23 | 1985-05-23 | Georg Fischer GmbH, 4020 Mettmann | Einrichtung zum Entgraten von als Gießerei-Kerne oder dergleichen ausgebildeten Werkstücken |
CA1214916A (en) * | 1983-09-06 | 1986-12-09 | Udo Kuehn | Method and apparatus for removing excess material from sand cores |
US4681600A (en) * | 1984-09-05 | 1987-07-21 | Extrude Hone Corporation | Cutting tool fabrication process |
JPH0421626Y2 (ja) * | 1987-02-06 | 1992-05-18 | ||
JPH0539804Y2 (ja) * | 1988-07-20 | 1993-10-08 | ||
US4956200A (en) * | 1988-11-21 | 1990-09-11 | The Burns & Russell Company | Texturing a mold surface |
US5814161A (en) * | 1992-11-30 | 1998-09-29 | Massachusetts Institute Of Technology | Ceramic mold finishing techniques for removing powder |
CN104550711A (zh) * | 2014-12-17 | 2015-04-29 | 江苏凌特精密机械有限公司 | 一种振动环制造工艺 |
CN112756561B (zh) * | 2020-11-25 | 2022-10-04 | 昆山中超自动化有限公司 | 一种击打型砂芯去毛边设备 |
Family Cites Families (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE7118607U (de) * | 1971-08-12 | Alcan Aluminiumwerke Gmbh | Leicht entfernbare Kerne und Form teile fur Gießereizwecke | |
US1991013A (en) * | 1932-04-23 | 1935-02-12 | Western Brick Company | Method and apparatus for coating the interior of mold surfaces |
US2174755A (en) * | 1936-07-14 | 1939-10-03 | Durite Plastics Inc | Manufacture of synthetic resin bonded abrasive articles |
US2294239A (en) * | 1938-04-09 | 1942-08-25 | Durite Plastics Inc | Abrasive article |
US2308854A (en) * | 1938-06-28 | 1943-01-19 | Norton Co | Abrasive article |
US2817603A (en) * | 1953-03-04 | 1957-12-24 | Myron A Coler | Method of producing electrically conductive article |
DE1009884B (de) * | 1955-07-08 | 1957-06-06 | Vaw Ver Aluminium Werke Ag | Verfahren zur Vorbehandlung von Werkstuecken aus Aluminium oder Aluminiumlegierungen zur Herstellung hochglaenzender, anodisch oxydierter Oberflaechen |
US3424607A (en) * | 1964-06-15 | 1969-01-28 | Kalb Ind Inc De | Atactic polyolefin release agents |
US3313067A (en) * | 1964-10-20 | 1967-04-11 | Gen Electric | Process for deflashing articles |
US3450551A (en) * | 1966-02-01 | 1969-06-17 | Sun Oil Co | Process for treating molds |
US3684466A (en) * | 1971-01-28 | 1972-08-15 | Joseph V Petrone | Organic polymer bonded tumbling chip |
BE791956A (fr) * | 1971-12-03 | 1973-03-16 | Tido Chemisch Tech Produkte G | Revetement a usage metallurgique |
DE2403828B2 (de) * | 1974-01-28 | 1975-12-04 | Ideal-Standard Gmbh, 5300 Bonn | Verfahren zum Entgraten von aus zwei Hälften gebildeten Sandkernen für die Gießereitechnik |
US4086067A (en) * | 1975-03-12 | 1978-04-25 | International Telephone And Telegraph Corporation | Porous sintered abrasive articles and method of manufacture |
DE2654167C3 (de) * | 1976-11-30 | 1979-10-04 | Robert Bosch Gmbh, 7000 Stuttgart | Verfahren zum Entgraten von Sandkernen für die Gießereitechnik |
DE2731802A1 (de) * | 1977-07-14 | 1979-02-01 | Klein Alb Kg | Verfahren und vorrichtung zum entgraten von sandkernen |
-
1982
- 1982-01-18 DE DE19823201284 patent/DE3201284A1/de not_active Withdrawn
-
1983
- 1983-01-04 DE DE8383100035T patent/DE3360306D1/de not_active Expired
- 1983-01-04 EP EP83100035A patent/EP0086321B1/de not_active Expired
- 1983-01-04 AT AT83100035T patent/ATE13985T1/de active
- 1983-01-14 US US06/457,987 patent/US4560586A/en not_active Expired - Fee Related
- 1983-01-18 ES ES519074A patent/ES519074A0/es active Granted
- 1983-01-18 JP JP58005405A patent/JPS58209444A/ja active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4005824C1 (en) * | 1990-02-23 | 1991-03-07 | Theodor Heimeier Metallwerk Kg, 4782 Erwitte, De | Method of deburring foundry cores - has cores placed in ring vibrator and grinding bodies added to these |
DE4019433C1 (en) * | 1990-06-19 | 1991-08-29 | Theodor Heimeier Metallwerk Kg, 4782 Erwitte, De | Removal of flash and application of wash coating to foundry cores - comprising circulating cores in ring vibrator to which grinding medium contg. two types of grinding body is added |
Also Published As
Publication number | Publication date |
---|---|
EP0086321A1 (de) | 1983-08-24 |
DE3201284A1 (de) | 1983-08-04 |
ES8308729A1 (es) | 1983-10-16 |
ATE13985T1 (de) | 1985-07-15 |
DE3360306D1 (en) | 1985-08-01 |
US4560586A (en) | 1985-12-24 |
JPS58209444A (ja) | 1983-12-06 |
ES519074A0 (es) | 1983-10-16 |
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