Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C33/00—Making ferrous alloys
  • C22C33/02—Making ferrous alloys by powder metallurgy
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C33/00—Making ferrous alloys
  • C22C33/02—Making ferrous alloys by powder metallurgy
  • C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
  • C22C33/0278—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements with at least one alloying element having a minimum content above 5%
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C33/00—Making ferrous alloys
  • C22C33/02—Making ferrous alloys by powder metallurgy
  • C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C38/00—Ferrous alloys, e.g. steel alloys
  • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
  • C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C38/00—Ferrous alloys, e.g. steel alloys
  • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
  • C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium with vanadium
• • 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
  • F16H—GEARING
  • F16H15/00—Gearings for conveying rotary motion with variable gear ratio, or for reversing rotary motion, by friction between rotary members
  • F16H15/02—Gearings for conveying rotary motion with variable gear ratio, or for reversing rotary motion, by friction between rotary members without members having orbital motion
  • F16H15/04—Gearings providing a continuous range of gear ratios
  • F16H15/06—Gearings providing a continuous range of gear ratios in which a member A of uniform effective diameter mounted on a shaft may co-operate with different parts of a member B
  • F16H15/32—Gearings providing a continuous range of gear ratios in which a member A of uniform effective diameter mounted on a shaft may co-operate with different parts of a member B in which the member B has a curved friction surface formed as a surface of a body of revolution generated by a curve which is neither a circular arc centered on its axis of revolution nor a straight line
  • F16H15/36—Gearings providing a continuous range of gear ratios in which a member A of uniform effective diameter mounted on a shaft may co-operate with different parts of a member B in which the member B has a curved friction surface formed as a surface of a body of revolution generated by a curve which is neither a circular arc centered on its axis of revolution nor a straight line with concave friction surface, e.g. a hollow toroid surface
  • F16H15/38—Gearings providing a continuous range of gear ratios in which a member A of uniform effective diameter mounted on a shaft may co-operate with different parts of a member B in which the member B has a curved friction surface formed as a surface of a body of revolution generated by a curve which is neither a circular arc centered on its axis of revolution nor a straight line with concave friction surface, e.g. a hollow toroid surface with two members B having hollow toroid surfaces opposite to each other, the member or members A being adjustably mounted between the surfaces
• • 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
  • F16H—GEARING
  • F16H55/00—Elements with teeth or friction surfaces for conveying motion; Worms, pulleys or sheaves for gearing mechanisms
  • F16H55/32—Friction members

Definitions

• the invention relates to a transmission component comprising a Powder Metallurgy type high alloy steel.
• a transmission component is known from EP-0462637A.
• a continious variable transmission is shown wherein a belt extends between two pulley's of varying effective diameter. At least one contact surface of a pully with the belt is covered with a layer realised through Powder Metallurgy. Starting from a base pulley, such layer is arranged during a later stage of manufacturing.
• Operational conditions of continous variable transmission show relatively low contact pressure between the belt and the pully. Operation is generally dry i.e. without the presence of a lubricant.
• the invention relates to an IVT component.
• IVT IVT of the toro ⁇ dal type and more particular the disk or rollers thereof.
• the contact surfaces of the disks, rollers respectively are subjected to high contact loadings under conditions wherein a lubricant is present.
• the contact pressure is considerably higher between the circumferential surface of the powder roller and raceway of the disk.
• High contact fatigue strength requirements are set as well as a requirement for static load capacity, without a lubrication film being present. It has been found that an ordinary rolling bearing steel does not meet these requirements.
• the invention aims to provide a component which has improved properties making it particular suitable for IVT disk and power roller components.
• said transmission component comprises a disk or roller of a toro ⁇ dal type IVT being integrally shaped through
• Integrally shaped is to be understood as fully comprising PM material. This in contrast to EP-0462637 wherein only a layer of PM material is provided. Only through integral manufacturing of a IVT component such as a disk and more preferably a power roller sufficient service life can be realised at the high contact fatigue loads revealing.
• the invention is particularly used for the manufacturing of power rollers of an INT. More particular the composition of the steel used for the IVT component comprises
• a PM M62 type steel comprising:
• the power metallurgy steel can be produced with any method known in the art. As example the following steps are given:
• powder metallurgy high alloy steels are subjected to a secondary hardening treatment.
• this is realised through austenising at 1205 ⁇ 5°C for 5-10 minutes followed by gas, oil or salt quenching and -tempering at about 550 °C.
• the hardness can be as high as 67 HRC with high temperature hardness properties.
• Fig. 1 shows an example of an IVT
• Fig. 2 shows a comparative graph for the contact stress
• Fig. 3 shows a comparative graph for blunt notch toughness.
• the CVT/IVT comprises input disks 1 connected to the output shaft of an engine and an opposed output disk 2 connected to a drive chain or further gear box components of a vehicle or any other item which has to be driven with a variable ratio.
• Power rollers 3 can be journalled on any shaft and the axis thereof is indicated by 4. This shaft can make a rotational movement in the sense of arrow 5. Through rotation of other rollers in the sense of arrow 5 the transmission ratio between the input and output disk will change. As shown in fig.
• each power roller as well as the raceways 8 and 9 are subjected to considerable loadings. Probably this is one of the reasons that up to now this technique was not generally accepted.
• the maximum contact stress between the circumferential surface of the power rollers and the related raceway could be as high as 4 GPa. This is far higher than the contact pressure encountered in usual rolling bearings.
• the tilting movement according to arrow 5 introduces slip of the rollers relative to the disks. Such a slip is not present in rolling bearings. Fatigue cracking and fracture due to repetitive bending stresses have been reported. The area of the disk within circle 11 is particular vulnerable. This means that the combined rolling contact fatigue strength of the traction surfaces (raceways) and fatigue fracture strength should be improved.
• Fig. 2 shows the rolling contact fatique life at different contact stresses.
• the usual rolling bearing steel ASTM A295 52100 (dotted line) is compared with the steel according to the invention PM M62 (continuous line).
• the number of cycle's (L50) is in million stress cycles.
• L50 the number of cycle's
• -.. is a 52100 steel whilst - ⁇ - shows PM M62. From this figure it is clear that in spite of the very high hardness of the PM M62 steel (67 HRC) , the toughness is no less than standard martensitic 52100 rolling bearing steel.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Materials Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• General Engineering & Computer Science (AREA)
• Rolling Contact Bearings (AREA)
• Friction Gearing (AREA)
• Powder Metallurgy (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=19769380

Family Applications (1)

Country Status (7)

Families Citing this family (3)

Family Cites Families (6)

• 1999
  • 1999-06-15 NL NL1012328A patent/NL1012328C2/nl not_active IP Right Cessation
• 2000
  • 2000-06-15 KR KR1020017015998A patent/KR20020012606A/ko not_active Withdrawn
  • 2000-06-15 EP EP00942541A patent/EP1204827A2/de not_active Ceased
  • 2000-06-15 WO PCT/NL2000/000418 patent/WO2000077268A2/en not_active Ceased
  • 2000-06-15 JP JP2001503707A patent/JP2003502496A/ja active Pending
  • 2000-06-15 AU AU57148/00A patent/AU5714800A/en not_active Abandoned
  • 2000-06-15 CN CN00808962A patent/CN1355874A/zh active Pending

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events