Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16J—PISTONS; CYLINDERS; SEALINGS
  • F16J9/00—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction
  • F16J9/06—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction using separate springs or elastic elements expanding the rings; Springs therefor ; Expansion by wedging
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16J—PISTONS; CYLINDERS; SEALINGS
  • F16J9/00—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction
  • F16J9/06—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction using separate springs or elastic elements expanding the rings; Springs therefor ; Expansion by wedging
  • F16J9/064—Rings with a flat annular side rail
  • F16J9/066—Spring expander from sheet metal
  • F16J9/069—Spring expander from sheet metal with a "C"-shaped cross section along the entire circumference

Definitions

• the invention relates to a two-part oil scraper ring for internal combustion engines, with a U-shaped spreading spring ring provided with axial incisions to form radially outward resilient legs and an annular body provided with parallel flanks and a tread, which is arranged between the resilient legs, in which installed condition only the ring body rests on the cylinder wall.
• a two-part oil scraper ring with a U-shaped expansion spring ring is known from DE 197 04 754 C1.
• a single lamella which is arranged between the legs of the spreading spring ring, permits an overall height of the oil control ring of approximately 1.5 mm.
• this solution has the advantage that a sufficient tangential force is exerted on the lamella by the spreading spring, so that the oil scraper effect can also be regarded as sufficient.
• a reduction in the overall height to or below 1.5 mm thus leads to an insufficient wiping action, as also described in DE 197 94 754 C2, so that overall heights of this magnitude for three-part rings can no longer be realized.
• the object of the present invention is to provide a two-part oil scraper ring which, in comparison with oil scraper rings of the generic type, permits a substantially improved oil scraper effect with a further reduced axial overall height.
• the object is achieved by the features of claim 1.
• the proposed construction of the oil scraper ring which consists of a U-shaped expansion spring ring with an annular body arranged between its legs, on the one hand advantageously achieves an overall height which is less than that of a two-part oil scraper ring, for example that according to DE 197 04 754 C1.
• a tangential force is exerted on the ring body by the spreading spring ring used, which is further increased by the fact that a certain design of the contact surface for the spreading spring legs is provided, so that an additional tangential force component is generated on the ring body, which leads to an improved oil wiping effect.
• the design of the contact surface permits a considerably simplified assembly of the ring body.
• FIG. 1 is a perspective view of the oil control ring according to the invention.
• Figure 2 is a perspective sectional view of the oil control ring in a first embodiment.
• Fig. 3 is a perspective sectional view of the oil control ring in a second embodiment.
• Fig. 4 is a perspective sectional view of the oil control ring in a third embodiment.
• an oil scraper ring 10 is formed from an expansion spring ring 1 with a u-shaped cross section, between the radially outward-pointing resilient legs 3 and 4 of which an annular body 7 with a running surface 9 is arranged.
• the spreading spring ring 1 has slots 2 on its radially inner side, so that the legs 3 and 4 are connected to one another via webs 5 designed as spring ring backs. Through the slots 2, the spread ⁇ spring ring 1 is resilient in the circumferential direction.
• the ring body 7, which is made of steel or cast iron and which can be designed as a minute nose ring, has flanks 7a and 7b which are oriented parallel to one another.
• the flanks have a roughness of Rz ⁇ 2 ⁇ m for a steel ring body and of Rz ⁇ 4 ⁇ m for a cast ring body.
• the ring body 7 has at its radially inner end, ie in the direction of the back of the expansion spring ring 1, an axially upward cutout 11 and an axially downward cutout 11, each with a contact surface 12, in which the legs 3 and 4 support resiliently.
• the contact surface 12 is aligned parallel to the flanks 7a and 7b, whereby according to a second exemplary embodiment according to FIG. 3 the contact surface 12 extends at an inclination angle ⁇ between 2 ° and 20 ° towards the stack plane.
• this enables simple assembly of the ring body and on the other hand creates an at least partially additional force component acting radially on the ring body for improved oil wiping.
• the recesses 12 in the ring body 7 are mirror-symmetrical to one another with the radial center axis as a mirror plane and have a height h a that is greater than the thickness D 1 of one leg of the spreading spring ring 1. This is in contrast to the existing state of the art a nominal height of the oil scraper ring 10 is realized, which is determined exclusively by the height h L of the ring body 7.
• the legs 3 and 4 of the spreading spring ring 1 are supported in a radial width B of the bearing surface 12, which corresponds to approximately one third of the total radial width of the lamellae, so that adequate guidance is ensured.
• radially extending oil grooves 6 are introduced on the circumferential side at an angular distance of 20 °, that is to say a total of 18 pieces, through which oil to be stripped from the ring body 7 from the cylinder wall is conveyed to the radially inner side of the spreading spring ring and through which Incisions 2 is transported to the crankshaft-side engine compartment.
• the cutouts 11 of the ring body 7 are designed such that the side 14 of the ring body facing away from the tread 9 rests against the back of the expansion spring ring 1, as a result of which the radial width B of the contact surface 12 can be increased.
• the oil to be wiped off the cylinder wall is transported away by the radially extending oil grooves 6 directly via the incisions 6 to the engine compartment on the crankshaft side.
• the ring body 7 can usually be treated by means of a gas nitriding process (GNS) to form a nitride layer.
• GFS gas nitriding process
• a wear coating of the treads 9 can also be applied by a PVD process, for example a CrN coating.
• the oil scraper ring 10 is inserted with sufficient play in the oil ring groove of a piston, only the ring body being in contact with the cylinder wall in the installed state.
• the expansion spring ring 1 is stretched to a smaller diameter, in which it is compressed in the circumferential direction, so that the resulting radial spring force presses the ring body 7 against the cylinder wall, the special design of the recess 11 for receiving the legs 3 and 4 of the Spreading spring washers 1 an axial height for a two-part oil control ring can be realized, which is less than 1.5 mm.
• Di leg thickness h L nominal height of the oil contact ring h A axial height of the recess

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Pistons, Piston Rings, And Cylinders (AREA)
• Rolling Contact Bearings (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=37114548

Family Applications (1)

Country Status (7)

Families Citing this family (6)

Family Cites Families (19)

• 2005
  • 2005-08-06 DE DE102005037205A patent/DE102005037205A1/de not_active Withdrawn
• 2006
  • 2006-07-18 WO PCT/DE2006/001239 patent/WO2007016894A1/de active Application Filing
  • 2006-07-18 EP EP06761816A patent/EP1910717A1/de not_active Withdrawn
  • 2006-07-18 BR BRPI0614384-9A patent/BRPI0614384A2/pt not_active IP Right Cessation
  • 2006-07-18 CN CNA2006800288582A patent/CN101238313A/zh active Pending
  • 2006-07-18 JP JP2008525378A patent/JP2009504960A/ja active Pending
  • 2006-07-18 US US11/990,046 patent/US20080309022A1/en not_active Abandoned

Non-Patent Citations (1)

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