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
• • 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
  • F01P3/00—Liquid cooling
  • F01P3/22—Liquid cooling characterised by evaporation and condensation of coolant in closed cycles; characterised by the coolant reaching higher temperatures than normal atmospheric boiling-point
  • F01P2003/2278—Heat pipes
• • 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
  • F05C2251/00—Material properties
  • F05C2251/04—Thermal properties
  • F05C2251/048—Heat transfer

Definitions

• the invention relates to a cooling channel piston for an internal combustion engine having heat pipes, with a forged piston head comprising a combustion recess in the piston head, an annular wall with a ring section and a cooling channel surrounding the ring section and closable by means of a cover, wherein in the cooling channel Distributed on its circumference a plurality of Kolben ⁇ directed towards the bottom holes are arranged, and has a piston skirt auf ⁇ has, which is connected to the piston head attached to the piston hubs.
• US Pat. No. 5,454,351 and DE 32 05 173 A1 describe light-metal pistons for an internal combustion engine which use so-called heat pipes for dissipating heat from the hot piston regions, ie the air-tight and pressure-tight sealing of a slightly evaporating cooling liquid, such as preferably water or else ammonia, glycol or the like.
• the existing copper heat pipes are circumferentially equally distributed holes that are introduced in the crankshaft side piston crown area, used or eing ⁇ poured, the holes extend to the level of the ring section. In the area of the piston hubs, the heat pipes are slightly bent to allow the piston pin to be fitted in the piston.
• the known manner of operation of the heat pipes consists in the evaporation of the liquid located in the heat pipe on the "hot" side - evaporator side - by absorption tion of the heat of the area to be cooled
• the steam formed flows to the "cold" side - the condenser side - of the heat pipe, where they change their liquid heat of vaporization due to the temperature drop between the hot and the cold side again in the liquid state on the cold side is by injection of Kuhlol from the crankshaft space of the internal combustion engine removes the evaporation heat
• Kuhlol from the crankshaft space of the internal combustion engine
• the invention has for its object to further develop a Kuhlkanalkolben of the type mentioned so that an improved heat dissipation of the heat-loaded piston areas achieved and thus the occurrence of thermi shear stresses is prevented
• this object is achieved by arranging liquid-filled heat pipes provided with an evaporator and condenser side in the boreholes of the cooling channel, the arrangement being such that the evaporator sides on the piston bottom end of the bores and the condenser sides in the closed cooling duct end up
• FIG. 2 shows a half-side sectional view of a piston head with cooling channel and heat pipe in a first arrangement according to the invention
• FIG. 3 shows a half-side sectional view of a piston head with a cooling channel and heat pipe in a second arrangement according to the invention
• FIG. 4 shows a half-side sectional view of a piston head with a cooling channel and heat pipe in a third arrangement according to the invention
• Fig. 5 is a sectional view taken along the line AA of FIG. 1;
• Fig. 6A is a sectional view of a heat pipe in a first embodiment
• Fig. 6 B is a sectional view of a heat pipe in a second embodiment.
• the one-piece cooling channel piston according to the invention with heat pipes consists of a forged piston head 10 made of steel with a combustion bowl 2 in its piston crown 1, an annular wall 4 with ring section 3, a closed at the height of the ring section closed cooling channel 7, as shown in Fig. 1.
• a piston skirt is connected to the hubs attached to the piston head, analogously to the representation of the figures according to WO 2004/029443 A1.
• the forged piston is manufactured according to the method according to EP 0 799 373 B1, wherein boreholes 5 are provided in the cooling channel 7, which are distributed on the circumference according to the impingement of the combustion jets and in the direction of the piston bottom, ie parallel to the piston axis A, are introduced, as can be seen from the Thomasdar ⁇ position shown in FIG. 5.
• the closing of the cooling channel 8 by means of a cooling oil inlet and outlet cover is provided, the depth B of ⁇ Boh ⁇ stanchions 5 is designed such that a wall ridge 9 formed between the piston head 1 and the bottom-side end of the bores.
• heat pipes heat pipe 6 have a steel shell and are made of a cylindrical base 6f and a either conical or cylindrical head portion 6c formed head and base have inside a cylindrical cavity , the evaku ⁇ ated and is befullt with a certain amount of coolant 6g, for example water, the coolant, particularly water, must be degassed bar before filling under vacuum at a pressure of 10 "4 to 10" 5 to cavitation as a result
• coolant 6g for example water
• the coolant particularly water
• the heat pipes are filled up to half their volume with Kuhlstoff headboard 6c and lower part 6f of the heat pipes 6 are connected via the connection f
• the evaporator side is referred to as the hot side 6a and the capacitor side 6b as the cold
• the diameters of the heat pipes 6 are about 3 to 10% of the piston diameter (D k0
• the heat pipes 6 filled with coolant are introduced into the bores 5 with a cylindrical head part such that the evaporator sides 6a at the piston bottom end of the bores 5 and the condenser sides 6b in the closed end Kuhlkanal 7 ends
• the heat flow thus takes place from the piston head 1 via the wall web 9 and the outer steel shell of the evaporator 6a to the inner wall of the steel shell and evaporates by absorbing the heat the coolant
• the steam formed parts flow to the condenser side 6b of the heat pipes 6, where they deliver their as a result of the temperature gradient between the evaporator and condenser side, latent heat of vaporization returns to the liquid state.
• the use of the bores 5 introduced in the piston head 10 can also be regarded as a cylindrical head part 6d, which is fastened to a heat pipe lower part 6f which is fastened to the cooling channel end of the bore 5 by means of a friction welding, screwing or adhesive connection. is connected.
• the bore 5 thus forms the evaporator side 6a and the friction-welded lower part 6f forms the condenser side 6b of the heat pipes.
• the head parts 6c of the heat pipes 6 are conical in shape.
• the bores 5 introduced in the cooling channel 7 toward the piston crown 1 run as far as the piston crown as a continuous bore which, in the region of the piston crown, likewise has a conical shape for receiving the heat pipes 6.
• the upper bottom surface of the evaporator sides 6a also forms part of the piston bottom itself, whereby a heat dissipation, as described above, is realized particularly effectively.
• the condenser sides 6b also end here in the cooling oil of the cooling channel 7.
• the condenser sides 6b end using conical headers in the crankshaft end of the engine compartment, ie the heat pipes are guided through the cover 8 of the cooling channel and injected by one or more cooling oil nozzles arranged there (not illustrated). This ensures that not all of the amount of heat absorbed on the combustion chamber side is dissipated to the cooling oil located in the cooling channel 7. ben and thus remains in the piston head 10, but the main portion of the heat flow is transported away from the piston head 10.
• these preferably consist of the same steel material, the bores 5 and the outside diameter of the heat pipes being designed such that the heat pipes 6 communicate with the piston head 10 by means of a press fit or by means of a soldering or welding connection, also Reibsch doneitati connected.
• the bores 5 for receiving thetons ⁇ tubes 6 in addition to a parallel to the piston axis A course also under an inclination to the piston axis, depending on the design of the combustion bowl or wall thickness between the combustion bowl 2 and cooling channel 7 may be arranged (not illustrated) so that the evaporator side 6a of the heat pipes forms a wall web 9 or directly a part of the wall of the combustion mold, according to the preceding embodiments, the condenser side ending in the cooling channel 7.

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)
• Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=35134836

Family Applications (1)

Country Status (8)

Families Citing this family (27)

Family Cites Families (25)

• 2004
  • 2004-08-11 DE DE102004038946A patent/DE102004038946A1/de not_active Withdrawn
• 2005
  • 2005-08-10 JP JP2007525163A patent/JP4909269B2/ja not_active Expired - Fee Related
  • 2005-08-10 EP EP05774024A patent/EP1778965A1/de not_active Withdrawn
  • 2005-08-10 KR KR1020077005457A patent/KR101210098B1/ko not_active IP Right Cessation
  • 2005-08-10 US US11/659,986 patent/US7603977B2/en not_active Expired - Fee Related
  • 2005-08-10 CN CNA2005800303253A patent/CN101018942A/zh active Pending
  • 2005-08-10 WO PCT/DE2005/001411 patent/WO2006015585A1/de active Application Filing
  • 2005-08-10 BR BRPI0514305-5A patent/BRPI0514305A/pt not_active Application Discontinuation

Non-Patent Citations (2)

Also Published As

Similar Documents

Legal Events