EP4363738A1 - Einschichtiger trockenreibbelag - Google Patents

Einschichtiger trockenreibbelag

Info

Publication number
EP4363738A1
EP4363738A1 EP22737453.5A EP22737453A EP4363738A1 EP 4363738 A1 EP4363738 A1 EP 4363738A1 EP 22737453 A EP22737453 A EP 22737453A EP 4363738 A1 EP4363738 A1 EP 4363738A1
Authority
EP
European Patent Office
Prior art keywords
fibers
friction lining
weight
friction
fillers
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.)
Pending
Application number
EP22737453.5A
Other languages
English (en)
French (fr)
Inventor
Isabelle Alix
Kevin FOUYER
Philippe Perret
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.)
Valeo Materiaux de Friction SAS
Original Assignee
Valeo Materiaux de Friction SAS
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 Valeo Materiaux de Friction SAS filed Critical Valeo Materiaux de Friction SAS
Publication of EP4363738A1 publication Critical patent/EP4363738A1/de
Pending legal-status Critical Current

Links

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
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D69/00—Friction linings; Attachment thereof; Selection of coacting friction substances or surfaces
    • F16D69/02—Composition of linings ; Methods of manufacturing
    • F16D69/025—Compositions based on an organic binder
    • F16D69/026—Compositions based on an organic binder containing fibres
    • 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
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D13/00—Friction clutches
    • F16D13/58—Details
    • F16D13/60—Clutching elements
    • F16D13/64—Clutch-plates; Clutch-lamellae

Definitions

  • the present invention relates to a single-layer dry friction lining for a motor vehicle clutch device.
  • the friction lining according to the invention can thus in particular be implemented in dry transmissions such as a double dry clutch, clutch for manual transmission or robotic gearbox (AMT).
  • AMT robotic gearbox
  • a motor vehicle clutch operating dry generally comprises a friction disc bearing on each of its faces friction linings fixed to a possibly common support.
  • the support is fixed to a splined hub in mesh with an input shaft of a gearbox.
  • a torsion damper is generally interposed between the friction lining support(s) and the splined hub.
  • a progressive device is conventionally placed between the two friction linings.
  • the friction disc is, in service, placed between, on the one hand, a reaction plate connected directly or indirectly to the crankshaft of the engine of the vehicle and, on the other hand, a pressure plate of a clutch mechanism comprising a cover connected to the reaction plate and an annular diaphragm, axially urging the pressure plate which is connected in rotation to the cover while being able to move axially with respect to the latter in a limited manner.
  • a friction lining must make it possible to transmit a torque from the engine to the gearbox and vice versa.
  • the packing must have good mechanical resistance under different stresses, radial, axial, circumferential, with or without shearing of the materials under load and with or without thermal stresses and good thermal resistance, that is to say resist mechanically after thermal damage, not losing its ability to rub (no slippage) at high temperature.
  • a friction lining must have a relatively high and homogeneous coefficient of friction on the surface of the friction lining to transmit engine torque to the gearbox.
  • a friction lining must also have good wear resistance, i.e. its coefficient of friction must also remain substantially constant over the length of clutch life (at least after an initial break-in stage). The thickness of the friction lining should not vary too much during the life of the clutch either.
  • friction materials are composite materials, they will wear out during shift cycles at the interface of the cast iron counter-materials.
  • materials that do not contain asbestos an abrasive effect of glass fibers on cast iron is known. This aggressiveness can lead to vibratory phenomena making engagements unpleasant.
  • This is particularly important for dry double clutch friction linings which therefore require friction materials with a high level of comfort given the automatic control of the gearbox. This level of comfort must be stable over time, that is to say throughout the duration of use of the materials in the clutch.
  • a thermal safety exists, controlled by the control software of the gearbox, the friction materials must therefore have thermal stability at higher temperatures.
  • the invention aims to propose a friction lining which makes it possible to solve the aforementioned problems.
  • the subject of the invention is a single-layer dry friction lining for a motor vehicle clutch device, comprising:
  • thermosetting resin - 45 to 55% by weight relative to the total weight of the lining of a reactive material, said material comprising a thermosetting resin, rubber and lubricating fillers,
  • a fibrous base material comprising glass fibers, organic fibers and metal fibers.
  • said filling having a mass ratio between the organic fibers and the glass fibers of between 0.05 and 0.25, preferably between 0.1 and 0.2, wherein the metal fibers are copper fibers present in a percentage by weight of between 1 and 10%, preferably between 5 and 10% by weight relative to the total weight of the lining.
  • the friction lining according to the invention thus makes it possible, thanks to a specific mass ratio between the organic fibers and the glass fibers associated with a specific quantity of copper fibers, to obtain improved thermal, mechanical and comfort performance.
  • Such a combination thus leads to an improvement in the thermal resistance in use and in the mechanical resistance, in particular after thermal abuse, in the level of friction, a stabilization of the level of comfort after wear and a limitation of the aggressiveness of the material vis-à-vis screws against materials.
  • the present invention also relates to a clutch device for a motor vehicle comprising a friction lining according to the present invention.
  • FIG. 1 represents the mechanical resistance (revolutions per minute before breaking) as a function of the mass ratio between the organic fibers and the glass fibers of three friction linings.
  • FIG. 2 represents the ability to transfer torque under severe conditions with high loads, namely stress on a slope with an unladen trailer (hill start).
  • FIG. 3 represents the evolution of the excitation coefficient as a function of the temperature of two friction linings.
  • FIG. 4 represents the mechanical resistance (revolutions per minute before breaking) as a function of the mass ratio between the organic fibers and the glass fibers of three friction linings.
  • FIG. 5 represents the ability to transfer torque under severe conditions with high loads, namely stress on a slope with an unladen trailer (hill start).
  • FIG. 6 represents the evolution of the excitation coefficient as a function of the temperature of three friction linings. In the present invention, unless otherwise indicated, all the (%) indicated are percentages (%) by weight relative to the total weight of the friction lining.
  • thermal abuse is meant to describe a lining after stressing up to 360° C. for 3 hours. This corresponds to a temperature at which the organic binders of a friction lining can be damaged by breaking chemical bonds and reduce the centrifugation resistance of the materials.
  • any interval of values designated by the expression "between a and b" means the range of values going from a to b (i.e. including the strict limits a and b).
  • the friction lining according to the present invention has a mass ratio between the organic fibers and the glass fibers, that is to say the mass of the organic fibers divided by the mass of the glass fibers, of between 0.05 and 0 .25, preferably between 0.1 and 0.2.
  • the fibrous base material includes glass fibers, organic fibers and metal fibers. These fibers are continuous threads and ensure resistance to centrifugal force and provide the thermal properties of the material. By continuous fibers, we mean fibers having essentially discontinuities only at the ends of the yarn.
  • the organic fibers are chosen from the group consisting of polyacrylonitrile (PAN), cellulose, aramid, hemp, flax fibers and mixtures thereof.
  • the organic fibers consist of polyacrylonitrile fibers.
  • the friction lining is free of carbon fibers.
  • carbon fibers have a relatively high cost and degrade friction at high temperature.
  • Carbon fibers is understood to denote, within the meaning of the present invention, fibers which consist only of carbon. A carbon fiber is therefore different from a fiber comprising carbon, as can be the organic fibers chosen from the group consisting of fibers of polyacrylonitrile (PAN), cellulose, aramid, hemp, flax and their mixtures.
  • the glass fibers can be roving and/or textured.
  • the fibers are said to be of the Roving type when they are grouped together in the form of a strand by sizing. Textured or volumized fibers are derived from Roving fibers by opening part of their volume, by injecting air. This has the effect of allowing better impregnation of the fibers towards the core or the core with the matrix (here the reagent containing the resins, rubber and fillers).
  • the glass fibers are present in the friction lining in a percentage by weight of between 30 and 45% relative to the total weight of the lining, preferably strictly greater than 30%.
  • the glass fibers have a linear density of between 600 and 2500 tex.
  • the organic fibers have a linear density of between 400 and 800 tex, preferably about 600 tex.
  • the copper fibers have a section between 100 and 200 ⁇ m.
  • the friction lining has an apparent density or hydrostatic density in a solvent such as water, of between 1.7 and 1.85 g/cm 3 .
  • the thermosetting resin is phenolic resin, for example of the novolac type, and/or melamine formaldehyde.
  • a high molecular weight resin will be used, that is to say from 2000 to 6000 g/mol.
  • the rubber latex is of the nitrile-butadiene (NBR) type and can be carboxylated or non-carboxylated.
  • NBR nitrile-butadiene
  • the resin, the rubber and the lubricating fillers are present in an amount by weight of between 35 and 45% relative to the total weight of the lining.
  • the reactive material further comprises resin, rubber and lubricating fillers, a vulcanization catalyst and other fillers.
  • the vulcanization catalyst is sulfur or zinc oxide.
  • the other fillers are advantageously chosen from so-called “friction” fillers.
  • such fillers may be chosen from carbon black, barium sulphate, activated carbon, kaolin, hollow microspheres (in particular glass) or calcium carbonate.
  • the lubricating fillers consist of mineral fillers and/or graphite according to a percentage by weight of between 3 and 10% relative to the total weight of the lining, preferably between 3 and 8%.
  • the fibrous base material is impregnated by the reactive material which can also be called aqueous cement i.e. the impregnating cement penetrates the space between the different fibers of a yarn, around the fibers, around a strand of fibers and/or at the heart of said fibers.
  • the mineral lubricating fillers consist of sulphides of metals preferably chosen from the group consisting of iron sulphide, copper sulphide, zinc sulphide, molybdenum disulphide, tin sulphide, tin disulphide and mixtures thereof.
  • the graphite is for example synthetic or natural graphite.
  • the graphite represents between 30 and 100% by weight of the lubricating filler.
  • the lubricating fillers have different densities, the ratio of mass fraction of lubricating fillers between the least dense filler and the most dense filler being between 0.6 and 4.
  • the use of lubricating fillers of different densities makes it possible to to balance and stabilize the performance of the friction material in hot lubrication, and thus avoid vibratory phenomena causing discomfort. This has the added effect of providing the friction material with increased resistance to friction and wear.
  • the mass fraction ratio between the least dense filler and the most dense filler is understood to mean the quotient of the mass fraction of the least dense lubricating filler divided by the mass fraction of the most dense lubricating filler. dense.
  • a mass fraction ratio of the lubricating fillers between the least dense filler and the most dense filler lying within the specified range has the effect of distributing the lubricating fillers homogeneously in composition within the reactive material.
  • each charge is evenly distributed inside the reactive material.
  • the reactive material makes it possible to produce a friction material capable of regulating the vibrations in a balanced and stable manner in hot lubrication.
  • the mass fraction ratio of lubricating fillers between the least dense filler and the densest filler is greater than or equal to 1.25, preferably greater than or equal to 1.3, preferably less than or equal to 3, of preferably less than or equal to 2, preferably less than or equal to 1.8, preferably equal to 1.6.
  • the ratio of the mass fraction of the lubricating fillers between the graphite and the mineral fillers is greater than or equal to 1 and less than or equal to 3.
  • the mass fraction ratio of the lubricating fillers between the graphite and the densest mineral filler is higher or equal to 0.65 and less than or equal to 1, preferably equal to 0.8.
  • the particle size of the lubricating fillers is greater than or equal to 5 ⁇ m and less than or equal to 30 ⁇ m.
  • each lubricating filler defined by its chemical composition is made up of grains of variable diameter.
  • the median diameter of the grains has a diameter greater than or equal to 5 ⁇ m and less than or equal to 30 ⁇ m.
  • a fine grain size gives the friction material better abrasion resistance due to an increased contact surface between the grains and the rubber.
  • the particle size of the lubricating fillers is less than or equal to 20 ⁇ m.
  • the density of the lubricating fillers is greater than or equal to 2 and less than or equal to 8.
  • the reactive material can comprise one or more additives, for example at least one surfactant and/or at least one thickener.
  • a surfactant can be of the anionic type, for example a sodium, potassium or ammonium polyphosphate, or a sodium, potassium or ammonium sulphonate, or a sodium, potassium or ammonium sulphate.
  • a surfactant can be of the nonionic type, for example a polyacrylate or a polyvinylalcohol.
  • a thickener can include cellulose or calcium silicate.
  • the cellulose may be of the colloidal microcrystalline cellulose type.
  • the friction lining comprises (the % are given by weight relative to the total weight of the lining):
  • a reactive material comprising:
  • compositions of the fillings are expressed in percentage by weight, the % are given by weight based on the total weight of the filling.
  • the mass ratio between the polyacrylonitrile fibers and the glass fibers will be indicated by R ac / Mv.
  • Example 1 Comparative example relating to a packing whose ratio is outside of the claimed range (comparative example A1) and two fillings with the ratio RM ⁇ /M Y in the range of the present invention (example according to the invention B2 and B3)
  • the friction materials have the compositions given in the following table 1.
  • the reactive material comprising a mixture of phenolic and melamine/formaldehyde resin, NBR rubber, lubricating fillers and friction fillers is identical in the three examples and present according to a percentage by weight comprised between 45 and 55%.
  • Figures 1 and 4 represent the mechanical strength (revolutions per minute before rupture) as a function of the mass ratio between the polyacrylonitrile fibers and the glass fibers.
  • the friction linings B2 and B3 have improved mechanical strength compared to A1.
  • the tests carried out show that the friction linings (external diameter of 240mm, internal diameter of 160mm and thickness of 3.7 mm) according to the present invention burst after being heated to 200° C. after having reached 12,800 revolutions/min (B3) and 13,400 revolutions/min (B2) against 12,000 revolutions/min for the lining A1.
  • the composition of the materials makes it possible to maintain this level of resistance after stress at higher temperatures, in particular after thermal abuse.
  • Figures 2 and 5 represent the ability to transfer torque under severe conditions with high loads, namely stress on a slope with an empty trailer (hill start) as a function of the mass ratio between the polyacrylonitrile fibers and the glass fibers.
  • the friction materials are subjected to energy cycles simulating 12% hill starts.
  • the test begins with a phase of 300 running-in cycles at low surface energy (9KJ, 100°C), followed by a first test with x start-up cycles on a slope (each cycle lasts 60s with a surface energy of 101 kJ) until to slip (i.e.
  • Figures 3 and 6 represent the excitation coefficient (in N.m.s) as a function of temperature (°C).
  • a first phase of 100 cycles during which, for each cycle, an energy of 35kJ is brought to the material in continuous sliding with a temperature rise of 40 to 350°C is carried out (with 3 cycles per minute ).
  • the graph is the maximum value of all excitation points measured during the first phase.
  • trim B3 improves comfort with a negative excitation coefficient up to 350°C, while trim A1 is a source of vibration when the temperature exceeds 310°C.
  • Example 2 Comparative example relating to two fillings with a leather content which is outside the claimed range (comparative example C1 and C2) and the filling B2
  • the friction materials have the compositions given in Table 3 below.
  • the reactive material comprising a mixture of phenolic and melamine/formaldehyde resin, NBR rubber and lubricating fillers is identical in Examples B2 and C2 and present in a percentage by weight of between 45 and 55%.
  • C1 differs from B2 and C2, by the absence of lubricating fillers in the reactive material and of an SBR type rubber.
  • the friction lining B2 has improved mechanical strength compared to C1 and C2. Indeed, the tests carried out show that the friction linings outside the present invention burst after being heated to 200° C. after having reached 10,300 rpm (C1) and 11,300 rpm (C2) against 13,400 revolutions/min for seal B2
  • Figure 5 shows that for a material loaded with copper C2, the replacement of the reactive material has made it possible to greatly improve the thermal resistance of the material but the compromise is to be found between the properties of comfort, mechanical resistance and thermal resistance. .
  • An improved level of thermal resistance is obtained with B2 containing less copper, compared to C1.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Braking Arrangements (AREA)
  • Mechanical Operated Clutches (AREA)
EP22737453.5A 2021-06-29 2022-06-23 Einschichtiger trockenreibbelag Pending EP4363738A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR2107004A FR3124563B1 (fr) 2021-06-29 2021-06-29 Garniture de friction à sec monocouche
PCT/EP2022/067157 WO2023274833A1 (fr) 2021-06-29 2022-06-23 Garniture de friction à sec monocouche

Publications (1)

Publication Number Publication Date
EP4363738A1 true EP4363738A1 (de) 2024-05-08

Family

ID=77226920

Family Applications (1)

Application Number Title Priority Date Filing Date
EP22737453.5A Pending EP4363738A1 (de) 2021-06-29 2022-06-23 Einschichtiger trockenreibbelag

Country Status (5)

Country Link
EP (1) EP4363738A1 (de)
KR (1) KR20240027753A (de)
CN (1) CN117561383A (de)
FR (1) FR3124563B1 (de)
WO (1) WO2023274833A1 (de)

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4244994A (en) * 1979-06-21 1981-01-13 Raybestos-Manhattan, Inc. Laminated aramid fiber friction members
US4539240A (en) 1984-11-29 1985-09-03 Borg-Warner Corporation Asbestos free friction element
FR2844565B1 (fr) * 2002-09-12 2005-06-17 Valeo Materiaux De Friction Garniture de frottement destinee a equiper un dispositif mettant en oeuvre un frottement a sec, procede de fabrication d'une telle garniture de frottement et disque de friction equipe d'une telle garniture

Also Published As

Publication number Publication date
FR3124563A1 (fr) 2022-12-30
FR3124563B1 (fr) 2023-12-29
KR20240027753A (ko) 2024-03-04
WO2023274833A1 (fr) 2023-01-05
CN117561383A (zh) 2024-02-13

Similar Documents

Publication Publication Date Title
KR100918511B1 (ko) 나노입자들의 마찰 변형층을 구비한 마찰 물질
US7749562B1 (en) Porous friction material comprising nanoparticles of friction modifying material
US6194059B1 (en) Process for producing two-ply friction material
EP3397717B1 (de) Reibungsmaterial
FR2910947A1 (fr) Matiere de friction sans amiante
FR2802544A1 (fr) Materiau de friction a renfort fibreux
EP0896165A1 (de) Nass-Reibungsvorrichtung mit koaxialen Scheiben
US5478642A (en) Resin-based friction material comprising aramid, acrylic and carbon fibers in a phenolic resin binder
KR20180082589A (ko) 마찰재
WO2023274833A1 (fr) Garniture de friction à sec monocouche
EP3114165B1 (de) Reibbelag mit verbesserter verschleissfestigkeit, trockenreibungskupplung mit solch einem belag und verfahren zur herstellung solch eines belags und solch einer kupplung
EP4077530B1 (de) Wässriger imprägnierzement
FR2929364A1 (fr) Materiau de friction pour frottement en milieu liquide, dispositif et procede associes.
WO2019063316A1 (fr) Ciment d'impregnation aqueux
WO2019063317A1 (fr) Ciment d'impregnation aqueux
WO2016207068A1 (fr) Procede de fabrication d'un materiau de friction
Chen et al. Friction material/oil interface for slipping clutch applications
US5830309A (en) Resin-based friction material
JP2014077039A (ja) 湿式摩擦材及びその製造方法
FR2679971A1 (fr) Garniture d'embrayage a frottement a sec, sans amiante.
FR2661473A1 (fr) Garniture d'embrayage sans amiante.
WO2023137138A1 (en) Clutch assembly including calcined kaolin clay wet friction material with improved durability
FR3044058A1 (fr) Garniture de friction comprenant une resine melamine etherifiee
FR2844320A1 (fr) Garniture de friction pour disque d'embrayage
JP2003113880A (ja) 乾式摩擦材

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20231214

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR