WO2012079566A2 - Kolben für einen verbrennungsmotor und verfahren zu seiner herstellung - Google Patents
Kolben für einen verbrennungsmotor und verfahren zu seiner herstellung Download PDFInfo
- Publication number
- WO2012079566A2 WO2012079566A2 PCT/DE2011/002128 DE2011002128W WO2012079566A2 WO 2012079566 A2 WO2012079566 A2 WO 2012079566A2 DE 2011002128 W DE2011002128 W DE 2011002128W WO 2012079566 A2 WO2012079566 A2 WO 2012079566A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- piston
- bore
- cooling channel
- filling
- potassium
- Prior art date
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F3/16—Pistons having cooling means
- F02F3/18—Pistons having cooling means the means being a liquid or solid coolant, e.g. sodium, in a closed chamber in piston
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F3/16—Pistons having cooling means
- F02F3/20—Pistons having cooling means the means being a fluid flowing through or along piston
- F02F3/22—Pistons having cooling means the means being a fluid flowing through or along piston the fluid being liquid
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
- F01P1/00—Air cooling
- F01P1/04—Arrangements for cooling pistons
Definitions
- the present invention relates to a piston for an internal combustion engine, having a piston head and a piston skirt, wherein the piston head has a circumferential annular portion and in the region of the annular part a circumferential cooling channel, wherein the piston skirt has hub bores provided with piston bosses, which have hub connections on the underside of the piston head are arranged, wherein the piston hubs are interconnected via running surfaces.
- the object of the present invention is to develop a generic piston so that sets a more uniform temperature distribution between the piston head and the piston skirt during operation.
- the solution is that within a piston hub at least one axially outwardly closed bore is provided, which is arranged between a running surface and a hub bore that opens at least one bore in the cooling channel, and that the cooling channel and the at least one bore a filling containing sodium and / or potassium.
- the piston according to the invention is characterized in that the heat generated in the region of the piston crown is conducted via the piston head into the piston hubs and discharged via the comparatively large-area running surfaces.
- a uniform heat distribution over the entire piston is achieved during operation.
- a more effective cooling of the entire piston is achieved.
- four holes are provided, which are arranged between a running surface and a hub bore in order to achieve a particularly uniform temperature distribution in the piston.
- the at least one bore is expediently closed by means of a closure element which, for example, is pressed into the bore or welded to the piston in order to prevent the coolant from escaping.
- the filling with the coolant preferably has a filling level up to half the height of the cooling channel in order to achieve a shaker effect and thus a particularly effective cooling.
- the filling can consist of potassium, sodium or an alloy of both metals. Particularly useful is a filling of a potassium-sodium Alloy with 22 wt .-% sodium and 78 wt .-% potassium, since this alloy has a particularly low melting point.
- the filling may additionally contain lithium and / or lithium nitride. If nitrogen is used as a protective gas during filling, this can react with the lithium to lithium nitride and be removed in this way from the cooling channel.
- the filling may further contain sodium oxides and / or potassium oxides, if during the filling any existing dry air has reacted with the coolant.
- the piston according to the invention can consist of an iron-based material, for example a material from the group consisting of precipitation-hardening steels, tempered steels, high-strength cast iron and cast iron with lamellar graphite.
- Figure 1 shows an embodiment of a piston according to the invention, partially in
- Figure 2 is a section along the line II - II in Figure 1;
- Figure 3 is a section along the line III - III in Figure 1;
- FIG. 4 shows an enlarged partial view from FIG. 3.
- Figures 1 to 4 show an embodiment of a piston 10 according to the invention.
- the piston 10 may be a one-piece or multi-piece piston.
- the piston 10 may be made of a steel material and / or a light metal material.
- Figures 1 to 3 show an example of a one-piece box piston 10.
- the piston 10 has a piston head 11 with a combustion recess 13 having the piston head 12, a peripheral land 14 and a ring portion 15 for receiving piston rings (not shown) on. In the amount of the ring section 15, a circumferential cooling channel 23 is provided.
- the piston 10 further includes a piston stem 16 with piston bosses 17 and hub bores 18 for receiving a piston pin (not shown).
- the piston hubs 17 are connected via hub connections 19 with the bottom 11 a of the piston head.
- the piston hubs 17 are connected to one another via running surfaces 21, 22 (cf., in particular, FIG.
- the piston shaft 16 has four axial bores 24a, 24b, 24c, 24d in the exemplary embodiment.
- the bores 24a-d are each introduced into the piston hubs and arranged between a running surface 21, 22 and the hub bore 18.
- the bores 24a-d open into the cooling channel 23.
- the piston 10 may, for example, be cast in a conventional manner, wherein the cooling channel 23 and the bores 24a-d can be introduced in a conventional manner by means of a salt core. It is essential that at least one bore 24a has an opening 25 to the outside.
- the coolant 27, namely sodium, potassium or an alloy of both metals is filled through the opening 25 into the bore 24a.
- the coolant 27 is distributed in the cooling channel 23 and in the further holes 24b-d.
- the opening 25 is then sealed, in the embodiment by means of a pressed-steel ball 26.
- the opening 25 can also be closed, for example. By welding a lid or pressing a cap (not shown).
- the size of the holes 24a-d and the filling amount of the coolant 27 depend on the size and the material of the piston 10. On average, about. 10g to 40g coolant 27 per piston 10 required.
- the cooling capacity can be controlled via the amount of added coolant 27. Conveniently, results in the cooling passage 23, a level corresponding to approximately half the height of the cooling channel 23. In this case, during operation, the known shaker effect can additionally be used for effective cooling.
- the underside 11a of the piston head 1 can be cooled by injection with cooling oil.
- a lance is inserted through the opening 25 and purged by means of nitrogen or other suitable inert gas or by means of dry air.
- the coolant 27 for example sodium and / or potassium, solid at room temperature, it is pressed under protective gas (for example nitrogen, inert gas or dry air) through the opening 25 by means of a press so that the coolant 27 is wire-shaped into the bore 24a or let the cooling channel 23 press.
- protective gas for example nitrogen, inert gas or dry air
- Another method for filling the bore 24a is characterized in that after flushing with nitrogen, inert gas or dry air, the bores 24a-d and the cooling channel 23 are evacuated and the coolant 27 is introduced in a vacuum.
- the coolant 27 can move more easily in the cooling channel 23 back and forth and in the bores 24a-d in and out, since it is not hindered by existing inert gas.
- Another possibility for removing the protective gas from the cooling channel 23 or the bores 24a-d is to use nitrogen or dry air (ie essentially a mixture of nitrogen and oxygen) as protective gas and a small amount of the coolant 27 Lithium, according to experience about 1, 8mg to 2.0mg lithium per cubic centimeter gas space (ie volume of the cooling channel 23 plus volume of the holes 24a-d). While sodium and potassium react with oxygen to form oxides, the lithium reacts with nitrogen to form lithium. nitride. The protective gas is thus almost completely bound as a solid in the coolant 27.
- nitrogen or dry air ie essentially a mixture of nitrogen and oxygen
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Pistons, Piston Rings, And Cylinders (AREA)
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201190000988.1U CN203655459U (zh) | 2010-12-18 | 2011-12-15 | 用于内燃机的活塞 |
EP11833594.2A EP2652302B1 (de) | 2010-12-18 | 2011-12-15 | Kolben für einen verbrennungsmotor und verfahren zu seiner herstellung |
JP2013543525A JP6113075B2 (ja) | 2010-12-18 | 2011-12-15 | 内燃機関用のピストンおよび該ピストンの製造方法 |
US13/995,017 US8899208B2 (en) | 2010-12-18 | 2011-12-15 | Internal combustion engine piston having axially extending cooling bores |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE102010055161 | 2010-12-18 | ||
DE102010055161.9 | 2010-12-18 | ||
DE102011114105.0 | 2011-09-22 | ||
DE201110114105 DE102011114105A1 (de) | 2010-12-18 | 2011-09-22 | Kolben für einen Verbrennungsmotor und Verfahren zu seiner Herstellung |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2012079566A2 true WO2012079566A2 (de) | 2012-06-21 |
WO2012079566A3 WO2012079566A3 (de) | 2012-10-04 |
Family
ID=45974185
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/DE2011/002128 WO2012079566A2 (de) | 2010-12-18 | 2011-12-15 | Kolben für einen verbrennungsmotor und verfahren zu seiner herstellung |
Country Status (6)
Country | Link |
---|---|
US (1) | US8899208B2 (de) |
EP (1) | EP2652302B1 (de) |
JP (1) | JP6113075B2 (de) |
CN (1) | CN203655459U (de) |
DE (1) | DE102011114105A1 (de) |
WO (1) | WO2012079566A2 (de) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2014012531A1 (de) * | 2012-07-18 | 2014-01-23 | Mahle International Gmbh | Verfahren zur herstellung eines kolbens |
WO2014032644A3 (de) * | 2012-08-31 | 2014-04-24 | Mahle International Gmbh | Kolben für einen verbrennungsmotor |
Families Citing this family (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
USD737861S1 (en) * | 2009-10-30 | 2015-09-01 | Caterpillar Inc. | Engine piston |
DE102011113800A1 (de) * | 2011-09-20 | 2013-03-21 | Mahle International Gmbh | Kolben für einen Verbrennungsmotor und Verfahren zu seiner Herstellung |
DE102012017218A1 (de) * | 2012-08-31 | 2014-03-20 | Mahle International Gmbh | Kolben für einen Verbrennungsmotor |
WO2014071274A1 (en) * | 2012-11-02 | 2014-05-08 | Federal-Mogul Corporation | Piston with a cooling gallery partially filled with a thermally conductive metal-containing composition |
DE102013002895B4 (de) | 2013-02-20 | 2022-05-19 | Mercedes-Benz Group AG | Kolben für eine Hubkolben-Verbrennungskraftmaschine |
USD768207S1 (en) * | 2014-07-16 | 2016-10-04 | Federal-Mogul Corporation | Piston |
JP2018505341A (ja) | 2015-01-30 | 2018-02-22 | フェデラル−モーグル・リミテッド・ライアビリティ・カンパニーFederal−Mogul Llc | 封止された冷却ギャラリを備えるピストンおよびその構成方法 |
US10202936B2 (en) * | 2015-04-09 | 2019-02-12 | Tenneco Inc. | Zero oil cooled (ZOC) piston incorporating heat pipe technology |
DE102015220256A1 (de) * | 2015-10-19 | 2017-04-20 | Mahle International Gmbh | Verfahren zur Herstellung eines Kolbens |
CN106801647A (zh) * | 2017-01-25 | 2017-06-06 | 日照金港活塞有限公司 | 一种封闭冷却腔活塞 |
DE102017202462A1 (de) | 2017-02-15 | 2018-08-16 | Mahle International Gmbh | Verfahren zum Herstellen eines Kolbens |
DE102017205451A1 (de) | 2017-03-30 | 2018-10-04 | Mahle International Gmbh | Kolben einer Brennkraftmaschine |
DE102017211335A1 (de) * | 2017-07-04 | 2019-01-10 | Federal-Mogul Nürnberg GmbH | Verfahren zur Herstellung eines Kolbens für einen Verbrennungsmotor, Kolben für einen Verbrennungsmotor, Kolbenrohling zur Herstellung des Kolbens sowie Gießform oder Schmiedegesenk zur Herstellung eines Kolbenrohlings |
US11148189B2 (en) * | 2018-10-10 | 2021-10-19 | Race Winning Brands, Inc. | Forged piston with oriented grain flow |
CN110748434B (zh) * | 2019-11-29 | 2024-08-30 | 滨州渤海活塞有限公司 | 一种汽油机钢活塞及其制造方法 |
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FR647110A (fr) | 1927-05-25 | 1928-11-20 | Perfectionnements aux pistons, et notamment aux pistons en métaux ou alliages à faible dilatation, mais peu conducteurs, tels que surtout la fonte et l'acier | |
GB310334A (en) * | 1928-04-23 | 1930-04-17 | Anton Gazda | Improvements in pistons |
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2011
- 2011-09-22 DE DE201110114105 patent/DE102011114105A1/de not_active Withdrawn
- 2011-12-15 US US13/995,017 patent/US8899208B2/en not_active Expired - Fee Related
- 2011-12-15 CN CN201190000988.1U patent/CN203655459U/zh not_active Expired - Lifetime
- 2011-12-15 WO PCT/DE2011/002128 patent/WO2012079566A2/de active Application Filing
- 2011-12-15 EP EP11833594.2A patent/EP2652302B1/de not_active Not-in-force
- 2011-12-15 JP JP2013543525A patent/JP6113075B2/ja not_active Expired - Fee Related
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None |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2014012531A1 (de) * | 2012-07-18 | 2014-01-23 | Mahle International Gmbh | Verfahren zur herstellung eines kolbens |
US20150176523A1 (en) * | 2012-07-18 | 2015-06-25 | Mahle International Gmbh | Method for producing a piston |
US9611804B2 (en) | 2012-07-18 | 2017-04-04 | Mahle International Gmbh | Method for producing a piston |
WO2014032644A3 (de) * | 2012-08-31 | 2014-04-24 | Mahle International Gmbh | Kolben für einen verbrennungsmotor |
JP2015526643A (ja) * | 2012-08-31 | 2015-09-10 | マーレ インターナショナル ゲゼルシャフト ミット ベシュレンクテルハフツングMAHLE International GmbH | 内燃機関用のピストン |
US9765728B2 (en) | 2012-08-31 | 2017-09-19 | Mahle International Gmbh | Piston for an internal combustion engine |
Also Published As
Publication number | Publication date |
---|---|
EP2652302B1 (de) | 2017-04-26 |
US8899208B2 (en) | 2014-12-02 |
EP2652302A2 (de) | 2013-10-23 |
JP6113075B2 (ja) | 2017-04-12 |
DE102011114105A1 (de) | 2012-06-21 |
US20130312695A1 (en) | 2013-11-28 |
CN203655459U (zh) | 2014-06-18 |
JP2013545927A (ja) | 2013-12-26 |
WO2012079566A3 (de) | 2012-10-04 |
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