EP0197449B1 - Piston à plusieurs parties pour une machine à combustion interne - Google Patents

Piston à plusieurs parties pour une machine à combustion interne Download PDF

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Publication number
EP0197449B1
EP0197449B1 EP86104232A EP86104232A EP0197449B1 EP 0197449 B1 EP0197449 B1 EP 0197449B1 EP 86104232 A EP86104232 A EP 86104232A EP 86104232 A EP86104232 A EP 86104232A EP 0197449 B1 EP0197449 B1 EP 0197449B1
Authority
EP
European Patent Office
Prior art keywords
piston
head
skirt
centering
end cover
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
EP86104232A
Other languages
German (de)
English (en)
Other versions
EP0197449A3 (en
EP0197449A2 (fr
Inventor
Manfred Schindler
Helmut Werner Burghardt
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.)
Ceramtec GmbH
Ficht GmbH
Original Assignee
Ceramtec GmbH
Ficht GmbH
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 Ceramtec GmbH, Ficht GmbH filed Critical Ceramtec GmbH
Priority to AT86104232T priority Critical patent/ATE53893T1/de
Publication of EP0197449A2 publication Critical patent/EP0197449A2/fr
Publication of EP0197449A3 publication Critical patent/EP0197449A3/de
Application granted granted Critical
Publication of EP0197449B1 publication Critical patent/EP0197449B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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 
    • F02F3/0015—Multi-part pistons
    • F02F3/0023—Multi-part pistons the parts being bolted or screwed together
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
    • F05C2201/00—Metals
    • F05C2201/02—Light metals
    • F05C2201/021—Aluminium
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
    • F05C2201/00—Metals
    • F05C2201/04—Heavy metals
    • F05C2201/0433—Iron group; Ferrous alloys, e.g. steel
    • F05C2201/0448—Steel

Definitions

  • the invention relates to a multi-part reciprocating piston for internal combustion engines as described and shown, for example, in DE-A-3218320.
  • DE-A-3218320 describes a reciprocating piston with a piston ring which is connected to the associated piston rod by means of an expansion screw. Piston shirt, piston skirt, piston crown, top land are made in one piece.
  • the reciprocating piston is used in internal combustion engines in which the translational movement of a piston is converted into a rotational movement by a crank-loop drive, in particular in which two pistons lie opposite one another.
  • Reciprocating pistons of internal combustion engines composed of several individual parts are known in many embodiments in so-called large engine construction.
  • the multi-part piston has been used there for a long time. The reasons lie in the various loads to which the motor piston is exposed.
  • the piston crown with its top land is exposed to alternating thermal stresses and static pressures.
  • the piston is generally subjected to high dynamic acceleration and deceleration forces.
  • the piston shirt is subject to great bending forces due to the high normal pressures.
  • the object of the invention is therefore to be seen in aligning the multiple parts of a reciprocating piston in such a way that the assembly or arrangement of a piston ring made of ceramic material in its intended annular groove in the top land of the piston crown, i.e. a piston ring, which is made of the material cannot be expanded without breaking, is easily possible.
  • the designed multi-part design should meet the requirements placed on such a piston with regard to thermal and dynamic resilience and improve its running properties and service life.
  • the construction of the reciprocating piston according to the invention allows the piston ring to be arranged in the annular groove provided in the top land of the piston crown without further ado before the assembly of its main parts.
  • the piston shirt made of ceramic material and the piston head made of ceramic material with the top land result in good sliding properties and a long service life.
  • the centering piece made of metallic material with the base plate and the upper end cover with the centering hub made of the same material not only center the reciprocating piston on the end of the piston rod but also guarantee a secure clamping of the main parts of the piston, since the elasticity of the metallic material can withstand the changing permanent loads that occur.
  • the large amount of heat accumulating on the piston crown during the combustion process is rapidly dissipated to the piston rod by heat flow, so that heat build-up in the piston is avoided.
  • the reciprocating piston according to the invention is particularly suitable for internal combustion engines in which the translational movement of two opposite, synchronous pistons is converted into rotation by a crank-loop drive, and both pistons are rigid with the associated piston rod, as described and illustrated, for example, in DE-C-920 758 .
  • piston design according to the invention and the piston arrangement described can also be used in piston machines in which the normal pressures of the thrust crank mechanism are absorbed by a crosshead slide, as a result of which the piston skirt is relieved.
  • piston engines have been proposed, for example, as so-called bio-gas engines.
  • the reciprocating piston consists essentially of a piston skirt 1 with a piston skirt 2, a piston skirt 3 with a top land 4, a centering sleeve 5 for radially fixing the two aforementioned main piston parts 1, and 3, 4, one in an annular groove 6 of the Top land 4 piston ring 7, a centering piece 8 with base plate 9 and from an end cover 10 with centering hub 11.
  • a piston rod is designated, at each end of which there is a reciprocating piston (the second reciprocating piston is not shown), both of which are rigidly connected to the piston rod 12. This is done, for example, by a cap screw (13) which is screwed into the piston rod 12.
  • the radial fixation of the reciprocating piston with respect to the piston rod 12 takes place by a snug fit 14 of the base plate 9 on the piston rod 12.
  • the base plate 9 fixes with the help of their centering piece 8, the centering hub 11 of the end cover 10.
  • the two parts 8, 9 and 10, 11 are secured against rotation by a dowel pin 15 which protrudes with its inner end into the piston rod 12.
  • the dowel pin 15 also forms a fuse for the cap screw 13.
  • the piston skirt 1 with the piston skirt 2, the piston skirt 3 with the top land 4, the resilient piston ring 7, which has an expansion slot 16, and the centering sleeve 5 are all made of a ceramic material which is thermally highly resilient and has good sliding properties .
  • the piston ring 7 is provided with an arc-shaped rounded portion 17 for the arrangement of a torsion pin 18 which prevents the piston ring 7 from moving.
  • a groove 19 is provided on the inner wall.
  • a fillet 20 is incorporated on the piston crown 3 to avoid notch stresses.
  • the top land 4 can be provided radially on the outside with a labyrinth seal in the form of rotational grooves 24 (FIG. 2).
  • Piston shirt, piston ring and piston crown are made of ceramic.
  • Shaped bodies made of silicon nitride and silicon carbide can be produced using the isostatic pressing process.
  • the piston crown can also be made from aluminum titanate.
  • piston skirt (1) and piston crown (3) are made of the same material, or if (1) (3), piston ring (7) and centering sleeve (5) are made of the same material.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Pistons, Piston Rings, And Cylinders (AREA)

Claims (7)

1. Piston formé de plusieurs éléments pour moteurs à combustion interne, dans lesquels le mouvement de translation du piston est converti en un mouvement de rotation par l'intermédiaire d'un mécanisme à manivelle et coulisse, et comportant une tige de piston (12) reliée rigidement au piston, la liaison incluant un système de vissage (13) associé à la tige de piston, caractérisé par une jupe de piston (1) réalisée en un matériau céramique et comportant un fond (2), une tête de piston (3) réalisée en un matériau céramique et comportant une zone de feu (4) possédant une gorge annulaire (6) formée par le fond (2) de la jupe de piston et la tête de piston (3) et servant à loger un segment fendu (7) réalisé en un matériau céramique, la tête de piston (3) étant en appui sur le fond (2) de la jupe de piston et le fond (2) de la jupe de piston et la tête de piston (3) étant fixés radialement par une douille commune de centrage (5) également réalisée en un matériau céramique, et en outre par une pièce de centrage (8), qui est fixée au moyen d'un ajustement serré (14) sur la tige de piston (12), est réalisée en un métal ou un alliage métallique, notamment un alliage d'aluminium, et comporte une plaque de base (9), sur lequel repose le fond (2) de la jupe de piston, et par un couvercle de fermeture (10), qui est réalisé avec le même matériau que la pièce de centrage (8) munie de la plague de base (9), est en appui sur la tête de piston (3), s'étend radialement jusqu'à la zone de feu (4) de la tête de piston et comporte un moyeu de centrage (11) fixé radialement par rapport à la pièce de centrage (9), moyennant la présence d'une fente axiale de séparation (23) entre la pièce de centrage (8) et le moyeu de centrage (11), le fond (2) de la jupe de piston et la tête de piston (3) étant serrés axialement entre le couvercle de fermeture (10) et la plaque de fond (9), par un système de vissage (13) associé à la tige de piston (12).
2. Piston selon la revendication 1, caractérisé en ce qu'une fente de dilatation (21 ou 22) est prévue respectivement aussi bien entre le moyeu de centrage (11) du couvercle de fermeture (10) et la douille de centrage (5), qu'entre le pourtour extérieur du couvercle de fermeture (10) et le pourtour intérieur de la zone de feu (4) de la tête de piston (3).
3. Piston selon la revendication 1 ou 2, caractérisé en ce qu'une gorge annulaire (19) servant à annihiler des contraintes est prévue au niveau de la jonction entre la jupe de piston (1) et son fond (2), dans la paroi intérieure de la jupe de piston.
4. Piston selon au moins l'une des revendications 1 à 3, caractérisé en ce qu'une gorge annulaire (20) servant à annihiler des contraintes provoquées notamment par des inégalités thermiques, est prévue dans la tête de piston (3), intérieurement, du point de vue radial, par rapport à la zone de feu (4) de la tête de piston, et ce dans la zone de la circonférence extérieure du couvercle de fermeture (10).
5. Piston selon au moins l'une des revendications 1 à 4, caractérisé en ce que pour éviter une rotation de la plaque de fond (9) conjointement avec le couvercle de fermeture (10) ou son moyeu de centrage (11) par rapport à la tige de piston (12), il est prévu un goujon d'assemblage (15) qui d'une part est bloqué dans la tige de piston (12) et traverse la plaque de base (9) et d'autre part pénètre dans le moyeu de centrage (11) du couvercle de fermeture (10).
6. Piston selon au moins l'une des revendications 1 à 5, caractérisé en ce que la tête de piston (3) comporte, au niveau du pourtour extérieur de sa zone de feu (4), un élément d'étanchéité à labyrinthe, se présentant notamment sous la forme de rainures (24) formées par tournage.
7. Piston selon au moins l'une des revendications 1 à 6, caractérisé en ce que le segment (7) comporte, au voisinage de la zone de jonction (16), un évidement (17) s'étendant sur un arc de cercle et servant à loger une goupille de fixation (18).
EP86104232A 1985-04-04 1986-03-27 Piston à plusieurs parties pour une machine à combustion interne Expired - Lifetime EP0197449B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT86104232T ATE53893T1 (de) 1985-04-04 1986-03-27 Mehrteiliger hubkolben fuer brennkraftmaschinen.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE8510204U 1985-04-04
DE8510204U DE8510204U1 (de) 1985-04-04 1985-04-04 Mehrteiliger Hubkolben für Brennkraftmaschinen

Publications (3)

Publication Number Publication Date
EP0197449A2 EP0197449A2 (fr) 1986-10-15
EP0197449A3 EP0197449A3 (en) 1987-11-25
EP0197449B1 true EP0197449B1 (fr) 1990-05-02

Family

ID=6779583

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86104232A Expired - Lifetime EP0197449B1 (fr) 1985-04-04 1986-03-27 Piston à plusieurs parties pour une machine à combustion interne

Country Status (6)

Country Link
US (1) US4751871A (fr)
EP (1) EP0197449B1 (fr)
JP (1) JPS61232366A (fr)
AT (1) ATE53893T1 (fr)
CA (1) CA1272645A (fr)
DE (2) DE8510204U1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102011009094A1 (de) 2011-01-21 2012-07-26 Bertwin Geist Hubkolben für eine Hubkolbenmaschine sowie Hubkolbenmaschine, sowie Zylinder einer Hubkolbenmaschine

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4833977A (en) * 1986-05-07 1989-05-30 Volkswagen Ag Piston for internal combustion engine
US4955284A (en) * 1989-02-27 1990-09-11 Ingersoll-Rand Company Piston having ceramic parts
US4920864A (en) * 1989-04-14 1990-05-01 Jpi Transportation Products, Inc. Reinforced piston
US5076150A (en) * 1990-05-04 1991-12-31 Dresser-Rand Company Piston assembly with wear resistant piston ring lands
GB2246833B (en) * 1990-06-23 1994-05-25 T & N Technology Ltd Pistons for engines or motors
DE4301860A1 (de) * 1993-01-25 1994-09-22 Stefan Dipl Phys Stock Spezialkolben für Kolbenmaschinen
US5375567A (en) * 1993-08-27 1994-12-27 Lowi, Jr.; Alvin Adiabatic, two-stroke cycle engine
US6044819A (en) * 1996-03-06 2000-04-04 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Pistons and cylinders made of carbon-carbon composite materials
US5713333A (en) * 1996-10-21 1998-02-03 Cummins Engine Company, Inc. Wear-resistant fuel distributor rotor
JPH10292868A (ja) * 1997-04-18 1998-11-04 Honda Motor Co Ltd 液体ポンプの軸封機構
US20080289488A1 (en) 1999-04-01 2008-11-27 Peter Robert Raffaele Reciprocating fluid machines
US6076506A (en) * 1998-05-20 2000-06-20 Caterpillar Inc. Piston for use in an engine
AUPR459501A0 (en) * 2001-04-27 2001-05-24 Raffaele, Michael John Improvements in engines and components
DE102004018714B4 (de) * 2004-04-17 2013-04-25 Dr. Ing. H.C. F. Porsche Aktiengesellschaft Verfahren zur Herstellung eines Kolbens
DE102004018712B4 (de) * 2004-04-17 2013-04-25 Dr. Ing. H.C. F. Porsche Aktiengesellschaft Kolben für eine Brennkraftmaschine
EP1911952B1 (fr) * 2006-10-11 2017-11-22 Nissan Motor Co., Ltd. Moteur à combustion interne
EP2111549A1 (fr) * 2007-02-14 2009-10-28 Agilent Technologies, Inc. Appareil de pompage chlp ayant une chambre de piston et/ou de travail en carbure de silicium
JP7313505B1 (ja) * 2022-03-28 2023-07-24 Ｔｐｒ株式会社 ピストンユニット、トップランド部材、及びピストンユニット用部品の組合せ

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DE463748C (de) * 1928-08-03 Werke Kiel Akt Ges Deutsche Mit Kuehleinsatz versehener Kolben fuer Brennkraftmaschinen
GB119183A (en) * 1918-02-11 1918-09-26 Alphonse Soetens Improvements in or relating to Pistons.
US1668672A (en) * 1927-04-01 1928-05-08 Charles W Darrah Piston
US1956355A (en) * 1931-02-18 1934-04-24 Junkers Hugo Internal combustion engine
US1963725A (en) * 1933-09-08 1934-06-19 Perfect Circle Co Piston and piston ring
US2105950A (en) * 1936-03-07 1938-01-18 Ingersoll Rand Co Piston
US2471477A (en) * 1946-03-08 1949-05-31 Air Liquide Piston packing
US2657961A (en) * 1950-03-15 1953-11-03 Maschf Augsburg Nuernberg Ag Piston for internal-combustion engines
DE920758C (de) * 1951-12-21 1954-11-29 Heinz Boerner Zweitaktbrennkraftmaschine
US3136306A (en) * 1961-04-20 1964-06-09 Stevens Inst Technology Piston for a high performance internal combustion engine
DE2212922B2 (de) * 1972-03-17 1976-02-05 Karl Schmidt Gmbh, 7107 Neckarsulm Gebauter kolben fuer verbrennungskraftmaschinen
GB1439328A (en) * 1972-07-28 1976-06-16 Wellworthy Ltd Pistons and piston rings
US4242948A (en) * 1977-12-16 1981-01-06 Cummins Engine Company, Inc. Insulated composite piston
US4404935A (en) * 1981-04-27 1983-09-20 Kyocera International, Inc. Ceramic capped piston
DE3363676D1 (en) * 1982-03-05 1986-07-03 Feldmuehle Ag Positive displacement member of a piston pump
DE3218320A1 (de) * 1982-05-14 1983-11-17 Ficht GmbH, 8011 Kirchseeon Vorrichtung zum loesbaren befestigen der kolben an den kolbenstangen einer brennkraftmaschine
DE3301913C2 (de) * 1983-01-21 1985-05-09 Feldmühle AG, 4000 Düsseldorf Kolbenring für eine Brennkraftmaschine

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102011009094A1 (de) 2011-01-21 2012-07-26 Bertwin Geist Hubkolben für eine Hubkolbenmaschine sowie Hubkolbenmaschine, sowie Zylinder einer Hubkolbenmaschine
WO2012097893A1 (fr) 2011-01-21 2012-07-26 Geist, Bertwin Piston alternatif pour moteur à piston alternatif, et moteur à piston alternatif, et cylindre d'un moteur à piston alternatif

Also Published As

Publication number Publication date
US4751871A (en) 1988-06-21
ATE53893T1 (de) 1990-06-15
EP0197449A3 (en) 1987-11-25
DE8510204U1 (de) 1985-07-11
EP0197449A2 (fr) 1986-10-15
CA1272645A (fr) 1990-08-14
DE3670885D1 (de) 1990-06-07
JPH0587672B2 (fr) 1993-12-17
JPS61232366A (ja) 1986-10-16

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