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
  • F16H—GEARING
  • F16H57/00—General details of gearing
  • F16H57/04—Features relating to lubrication or cooling or heating
  • F16H57/0405—Monitoring quality of lubricant or hydraulic fluids
• • 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
  • F16H59/00—Control inputs to control units of change-speed-, or reversing-gearings for conveying rotary motion
  • F16H59/14—Inputs being a function of torque or torque demand
  • F16H2059/147—Transmission input torque, e.g. measured or estimated engine torque
• • 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
  • F16H59/00—Control inputs to control units of change-speed-, or reversing-gearings for conveying rotary motion
  • F16H59/36—Inputs being a function of speed
  • F16H2059/366—Engine or motor speed
• • 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
  • F16H59/00—Control inputs to control units of change-speed-, or reversing-gearings for conveying rotary motion
  • F16H59/36—Inputs being a function of speed
  • F16H59/38—Inputs being a function of speed of gearing elements
  • F16H2059/385—Turbine speed
• • 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
  • F16H41/00—Rotary fluid gearing of the hydrokinetic type
  • F16H41/24—Details
  • F16H41/30—Details relating to venting, lubrication, cooling, circulation of the cooling medium
• • 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
  • F16H45/00—Combinations of fluid gearings for conveying rotary motion with couplings or clutches
  • F16H45/02—Combinations of fluid gearings for conveying rotary motion with couplings or clutches with mechanical clutches for bridging a fluid gearing of the hydrokinetic type
• • 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
  • F16H59/00—Control inputs to control units of change-speed-, or reversing-gearings for conveying rotary motion
  • F16H59/68—Inputs being a function of gearing status
  • F16H59/72—Inputs being a function of gearing status dependent on oil characteristics, e.g. temperature, viscosity

Definitions

• TITLE Method for diagnosing oil wear in an automatic gearbox torque converter of a motor vehicle
• the invention relates generally to systems for diagnosing oil wear in hydromechanical transmission systems of automatic gearboxes of motor vehicles.
• a particularly interesting application of the invention relates to automatic gearboxes comprising a torque converter, for example fitted with a hydraulic torque converter bridging clutch, the English name of which is better known under the name "Lock”. - up ”, or automatic transmissions fitted with a wet double clutch.
• the invention also applies to any other type of vehicle provided with a clutch system using pressurized oil between a rotary drive element and a driven element, to provide lubrication of the rotating parts or to ensure the tightening of a clutch.
• Automatic transmissions include a torque converter for transferring energy from the engine output to the vehicle's driveline.
• FIG. 1 shows a torque converter 1 as well as an engine 2 and the start of the kinematic chain 3.
• This torque converter 1 comprises an impeller 5 connected to the engine crankshaft 6 and a turbine 7 connected to the kinematic chain. 3.
• the impeller 5 circulates the pressure-regulated oil 8 in order to set the turbine 7 connected to the kinematic chain in rotation.
• This system is necessary during sudden braking of the vehicle in order to prevent the vehicle from stalling. to a difference in speed between that of the engine 2 (speed COM), which continues to run, and that of the turbine 7 of torque converter 1 (speed wt), which has greatly slowed down its rotation.
• speed COM speed COM
• speed wt speed wt
• a bridging 10 of the impeller 5 with the turbine 7 is carried out, in order to secure these two parts and to synchronize the engine speed COM with the speed wt of the turbine 7 of the converter. couple 1.
• This bridging 10 is carried out in the torque converter 1, therefore in contact with the oil 8 present in the converter 1, and more widely present in the gearbox.
• the role of oil is manifold. It is used to turn the turbine, to lubricate certain parts of the gearbox and to apply certain hydraulic clutches and brakes of the gearbox.
• the aim of the present invention is therefore to overcome the drawbacks of the aforementioned systems.
• the object of the invention is therefore a method for diagnosing oil wear in an automatic gearbox torque converter of a motor vehicle comprising a comparison of the speeds of the engine and of the turbine of the torque converter. when the vehicle's torque converter is bridged.
• comparing the engine speed with that of the torque converter turbine can detect actual oil wear and alert the driver when the oil needs to be changed rather than at mileage. given. This also makes it possible to direct a mechanic when he receives a vehicle whose engine is generating a jerk. This allows him to change the oil knowingly rather than trying to repair the injection system, which is not necessarily damaged.
• the comparison of the speeds of the engine and of the turbine of the torque converter is carried out if there has been a verification step guaranteeing that the vehicle's torque converter is bypassed, and that the temperature of the oil in the gearbox. speed is greater than a predetermined temperature threshold, and that the engine torque is greater than a predetermined torque threshold.
• a significant difference in speed between the two speeds is detected if the value of the difference between the two speeds oscillates at a frequency within a predetermined frequency range. during a predetermined period and if the value of the amplitude of the difference between the two regimes exceeds a predetermined value threshold.
• an oil wear of the torque converter is diagnosed if the number of occurrences of the deviation significant speed between the engine and turbine speeds of the torque converter exceeds a predetermined occurrence threshold during a predetermined period or if the significant deviation continues beyond a predetermined time threshold.
• an alert signal perceptible by the driver is sent if oil wear in the torque converter has been diagnosed.
• the alert signal perceptible by the driver is a light signal emitted from the dashboard.
• at least one driving parameter of the vehicle and at least one parameter for detecting a significant difference in speed between the speeds of the engine and of the turbine of the torque converter used for diagnosing wear of the torque converter are stored.
• torque converter oil is also an oil wear diagnostic system of an automatic gearbox torque converter of a motor vehicle for the implementation of a method as defined above, comprising means for comparing the speeds of the engine and the turbine of the torque converter when the torque converter of the vehicle is bypassed.
• FIG 1 which has already been mentioned, illustrates a schematic section of a torque converter of a gearbox implementing a method according to the invention
• FIG 2 illustrates a flowchart representing the steps of the method according to the invention
• FIG 3 illustrates a graph showing torque converter engine and turbine speeds as a function of time during transmission oil wear.
• FIG. 1 a schematic view of an automatic gearbox torque converter 1 implementing a method according to the invention.
• the torque converter 1 is shown schematically in order to adapt to each type of existing torque converter architecture.
• a wet double clutch of an automatic gearbox has the essential characteristics of the torque converter necessary for implementing the method according to the invention.
• clutch systems are similar to the bridging system of a torque converter.
• the method detects one of the effects of the wear of the oil 8, consisting of a loss of adhesion of the impeller 5 with the turbine 7 when they are bridged. The presence of micro slips between the impeller 5 and the turbine 7 is thus detected when these two elements are bridged, which causes jerks in the COM engine speed.
• This method is advantageously implemented by an on-board computer of the vehicle which is for this purpose duly programmed to implement each of the steps of the method.
• the next step 16 is a step of comparing the speed of the COM engine with the speed of the turbine wt. During a perfect bridging, these two speeds COM and wt must be the same since the turbine 7 and the engine 2, via the impeller 5, are interdependent.
• the engine speed COM oscillates at a speed different from that of the turbine 7.
• the speed of the latter remains constant thanks to the inertia of the motor vehicle.
• FIG. 3 There is shown in FIG. 3 a graph having a timescale as abscissa and an angular speed scale as ordinate schematically representing the engine speed COM and the speed of the turbine wt while micro-slips take place. They are demonstrated during step 17, in which a significant difference is detected between the two regimes if the difference in value between the two regimes oscillates at a frequency F included in a predetermined frequency range and if the oscillation s 'performs at least during a predetermined period P, for example for a period P of two hundred milliseconds and for a frequency F between thirty and sixty hertz, and if the amplitude of the difference in value between the two regimes COM and wt exceeds a threshold S of predetermined value, for example of fifty revolutions per minute.
• a threshold S of predetermined value for example of fifty revolutions per minute.
• an oil wear 8 present in the torque converter 1 is diagnosed if the number of occurrences of the significant difference between the speeds COM and wt of the engine 2 and of the turbine 7 exceeds one.
• predetermined occurrence threshold for example ten occurrences, during a predetermined period, for example ten seconds, or if the significant speed deviation continues beyond a predetermined time threshold, for example ten seconds.
• a warning signal perceptible by the driver is sent during the following step 19. It may, for example, be an indicator light on the instrument panel or an audible signal in the passenger compartment of the vehicle.
• a notification can also be sent by message, electronic mail, or any other type of telecommunication to a computer terminal of the user, for example the mobile phone of the driver.
• a step 20 of memorizing at least one of the running parameters of the vehicle and at least one of the parameters for detecting a significant difference in speed between the CO M and wt speeds of the engine and of the turbine used for diagnosing oil wear 8 is carried out by a vehicle computer.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Quality & Reliability (AREA)
• Mechanical Engineering (AREA)
• Control Of Transmission Device (AREA)
• Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
• General Details Of Gearings (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=71111575

Family Applications (1)

Country Status (5)

Family Cites Families (6)

• 2020
  • 2020-03-24 FR FR2002875A patent/FR3108700B1/fr active Active
• 2021
  • 2021-03-18 BR BR112022019314A patent/BR112022019314A2/pt unknown
  • 2021-03-18 EP EP21712511.1A patent/EP4127522A1/de active Pending
  • 2021-03-18 WO PCT/EP2021/056992 patent/WO2021191050A1/fr unknown
  • 2021-03-18 CN CN202180030242.3A patent/CN115485491A/zh active Pending

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