Classifications

• • 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
  • F01P3/06—Arrangements for cooling pistons
  • F01P3/10—Cooling by flow of coolant through pistons
• • 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 
  • F02F3/0084—Pistons  the pistons being constructed from specific materials
• • 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
• • 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 
  • F02F2003/0007—Monolithic pistons; One piece constructions; Casting of pistons
• • 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

Definitions

• Cast light metal piston especially an aluminum piston
• the present invention relates to a cast light metal piston, in particular an aluminum piston for an internal combustion engine with a piston head and an adjoining piston shaft according to the preamble of claim 1.
• the invention also relates to an internal combustion engine equipped with such a piston.
• a generic piston for an internal combustion engine is known from DE 10 2007 020 447 A1, in which the shaft wall arranged on the pressure side is shorter in the circumferential direction of the piston than that on the pressure side
• Box walls rectilinear and oblique, wherein the distance of the box walls in the area of the pin bosses is greater than in the region of the pressure-side shaft wall.
• the present invention deals with the problem, for a
• Lightweight piston of the generic type to provide an improved embodiment, which is characterized in particular by a reduced weight and increased load capacity.
• the present invention is based on the general idea that a cast light metal piston, in particular an aluminum piston, for an internal combustion engine compared to previously known from the prior art cast aluminum pistons, better cooled by an additional cooling channel and thereby even easier to form, thereby the to reduce the work required for the movement of the piston.
• the cast light metal piston, in particular the aluminum piston has in a known manner a piston crown facing a piston crown and a adjoining piston shaft, which has two arranged on the pressure side and the counter-pressure side of the shaft walls to guide and two walls connecting these walls walls.
• the box walls are arranged obliquely to each other and taper toward each other in the direction of the piston crown.
• Such a light metal piston is already known for example from DE 10 2007 020 447 A1 under the name Mahle Evotec ® .
• such a light metal piston now additionally and for the first time has an annular circumferential cooling channel which permits effective cooling of the piston, in particular in a transition region between the piston
• Piston bottom and a circumferential ring section allows, with a thickness of the piston crown is additionally limited to a maximum of 4.5 mm.
• Piston bottom the cast light metal piston according to the invention compared to the previously known piston with cooling channel, can be significantly reduced in terms of its weight, which reduced in terms of thickness piston crown allows better heat dissipation and thus better cooling means of a known Anspritzkühlung.
• the annular circumferential cooling channel provides the necessary cooling in the ring part, which was not possible in previously known light metal piston due to the lack of cooling channel in this form. Due to the inclined box walls, the required strength can be easily achieved despite the thinner piston crown, the limits of the thickness of the piston crown are usually set by the particular casting process used. In the following, often only the term "piston" is used as a generic term for cast light metal pistons, in particular aluminum pistons.
• the thickness of the piston crown is at most 3.5 mm, preferably even only 2 or 3 mm.
• Such a thin piston crown is compared to previously from the prior Technically known piston plates significantly reduced in terms of its weight, due to the small thickness of a bottom-acting Anspritzksselung for rapid heat dissipation and thus for effective cooling of the
• Piston bottom provides.
• the cooling channel is made by means of a salt core.
• a salt core are used for many years in the casting of light metal piston / aluminum piston and are therefore a proven and proven means for producing such hollow cooling channel structures.
• the cooling channel is produced for example by means of a sand core.
• Cooling channel according to the invention individually, for example, with varying
• Diameter can be made.
• the two box walls run towards one another in the direction of the pressure-side shaft wall.
• a pressure side and a counter-pressure side is at
• inventive piston distinguished because whenever, when the ignition in the combustion chamber, the resulting gas pressure acts on the piston head, the piston is pushed or tilted by the inclined connecting rod to the side, with the result that one of the two shaft walls in their tread against the Inner wall of the cylinder bore is pressed.
• This skirt wall is referred to as arranged on the pressure side skirt wall.
• the shaft wall arranged on the pressure side can be thinner in its central region than in its edge regions assigned to the casing walls, which, for example, can even go so far that the skirt wall arranged on the pressure side is designed to be up to 50% thinner in its central region than in its edge regions assigned to the casing walls, which in turn can achieve a considerable reduction of the moving mass of the piston according to the invention. It is advantageous if the increase in the thickness of the skirt wall from its central region to its outer edge regions is continuous, whereby the stress load is evenly distributed within the shaft wall.
• the present invention is further based on the general idea of equipping an internal combustion engine with at least one such piston and in addition at least two injection nozzles per light metal piston
• piston cooling one of which is directed to an inlet / inlet of the cooling channel of the piston and the other to the piston crown.
• Injection nozzle thus promotes cooling fluid, that is to say engine oil, into the cooling channel, where it contributes in particular to the annular part of the
• the other Anspritzdüse is preferably directed to the piston head and thus cools this by direct injection with oil from below. Due to the small thickness of the
• This piston bottom can be effectively cooled, since the heat generated in the combustion chamber penetrates the piston bottom comparatively quickly and thus can be dissipated by the injected oil.
• the piston crown is additionally cooled from below by an injecting oil from a rotating crankshaft, in particular if the crankshaft dips into an oil sump of the crankshaft housing. All in all, thus, an internal combustion engine with comparatively light but nevertheless powerful pistons can be created, which requires significantly less energy for translational reciprocating movement of the pistons due to their reduced weight.
• FIG. 1 shows a piston according to the invention in a side view
• Fig. 4 is a sectional view through the piston according to the invention along the cutting plane B-B.
• the piston 1 now has an at least partially annular circumferential cooling channel 9, which according to FIGS. 3 and 4 in particular additionally cools a transition region between the piston head 2 and a ring section 10. in the
• Region of the ring portion 10, for example, a circumferential land 1 and 1 ring 12 are provided for receiving, for example, piston rings, not shown.
• the thickness d of the piston crown 2 is at most 4.5 mm.
• the thickness d of the piston crown 2 is preferably at most 3.5 mm, preferably even at most 3 mm or at most 2 mm.
• arranged on the pressure side DS shaft wall 4 is formed shorter in the circumferential direction of the piston 1 than the arranged on the back pressure side GDS shaft wall 5, wherein the two box walls 6, 7 in the direction of the pressure side Shank wall 4 converge.
• the two box walls 6, 7 run away from each other in the direction of the counter-pressure side skirt 5, of course, a running towards each other of the two box walls 6, 7 in the direction of the counter-pressure side skirt 5 is conceivable, so that in this case, the two box walls 6, 7 biconvex are arranged to each other.
• the cooling channel 9 can during casting of the light metal piston 1, in particular of the aluminum piston 1 'by means of a salt core or by means of a
• Sandkerns are prepared in the usual way.
• coolant in particular cooling oil
• this has an inlet 13 and a drain 14, which are shown in FIG.
• inlet and outlet 13, 14 can also be arranged vice versa.
• the coolant to be introduced into the cooling channel 9 for piston cooling for example engine oil
• piston 1, 1 characterize as follows: By an extremely thin piston head 2 connected to an additionally arranged cooling channel 9, the piston 1, 1' according to the invention can be with despite low weight represent higher strength.
• the inclined box walls 6, 7 cause the required rigidity and strength for a long life of the piston crown and thus allow low bottom wall thicknesses.

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)

Applications Claiming Priority (2)

Publications (1)

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ID=48050664

Family Applications (1)

Country Status (7)

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Citations (2)

Family Cites Families (17)

• 2012
  • 2012-03-07 DE DE102012203570A patent/DE102012203570A1/de active Pending
• 2013
  • 2013-03-06 US US14/383,226 patent/US10655561B2/en active Active
  • 2013-03-06 WO PCT/EP2013/054468 patent/WO2013131937A1/de active Application Filing
  • 2013-03-06 JP JP2014560348A patent/JP2015511674A/ja active Pending
  • 2013-03-06 EP EP13714864.9A patent/EP2823166A1/de not_active Withdrawn
  • 2013-03-06 CN CN201380012601.8A patent/CN104160127B/zh active Active
  • 2013-03-06 BR BR112014021986-9A patent/BR112014021986B1/pt active IP Right Grant

Patent Citations (2)

Non-Patent Citations (1)

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