WO2020141189A1 - Apparatus and method for controlling cam - Google Patents

Apparatus and method for controlling cam Download PDF

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Publication number
WO2020141189A1
WO2020141189A1 PCT/EP2020/050008 EP2020050008W WO2020141189A1 WO 2020141189 A1 WO2020141189 A1 WO 2020141189A1 EP 2020050008 W EP2020050008 W EP 2020050008W WO 2020141189 A1 WO2020141189 A1 WO 2020141189A1
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WO
WIPO (PCT)
Prior art keywords
pwm signal
cam
holding
region
learning
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.)
Ceased
Application number
PCT/EP2020/050008
Other languages
French (fr)
Inventor
YoungMo LEE
HaMyeong SONG
Jaewon Choi
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.)
Vitesco Technologies GmbH
Original Assignee
Vitesco Technologies GmbH
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 Vitesco Technologies GmbH filed Critical Vitesco Technologies GmbH
Priority to CN202080007891.7A priority Critical patent/CN113227562B/en
Priority to DE112020000316.7T priority patent/DE112020000316T5/en
Priority to US17/420,777 priority patent/US12110814B2/en
Publication of WO2020141189A1 publication Critical patent/WO2020141189A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L1/00Valve-gear or valve arrangements, e.g. lift-valve gear
    • F01L1/34Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift
    • F01L1/344Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear
    • F01L1/3442Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear using hydraulic chambers with variable volume to transmit the rotating force
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L13/00Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
    • F01L13/0015Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02DCONTROLLING COMBUSTION ENGINES
    • F02D13/00Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
    • F02D13/02Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
    • F02D13/0203Variable control of intake and exhaust valves
    • F02D13/0215Variable control of intake and exhaust valves changing the valve timing only
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02DCONTROLLING COMBUSTION ENGINES
    • F02D41/00Electrical control of supply of combustible mixture or its constituents
    • F02D41/24Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
    • F02D41/2406Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
    • F02D41/2425Particular ways of programming the data
    • F02D41/2429Methods of calibrating or learning
    • F02D41/2451Methods of calibrating or learning characterised by what is learned or calibrated
    • F02D41/2464Characteristics of actuators
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L1/00Valve-gear or valve arrangements, e.g. lift-valve gear
    • F01L1/34Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift
    • F01L1/344Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear
    • F01L1/3442Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear using hydraulic chambers with variable volume to transmit the rotating force
    • F01L2001/34423Details relating to the hydraulic feeding circuit
    • F01L2001/34426Oil control valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L1/00Valve-gear or valve arrangements, e.g. lift-valve gear
    • F01L1/34Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift
    • F01L1/344Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear
    • F01L1/3442Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear using hydraulic chambers with variable volume to transmit the rotating force
    • F01L2001/34423Details relating to the hydraulic feeding circuit
    • F01L2001/34426Oil control valves
    • F01L2001/3443Solenoid driven oil control valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L1/00Valve-gear or valve arrangements, e.g. lift-valve gear
    • F01L1/34Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift
    • F01L1/344Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear
    • F01L1/3442Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear using hydraulic chambers with variable volume to transmit the rotating force
    • F01L2001/34423Details relating to the hydraulic feeding circuit
    • F01L2001/34426Oil control valves
    • F01L2001/34433Location oil control valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L2201/00Electronic control systems; Apparatus or methods therefor
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L2800/00Methods of operation using a variable valve timing mechanism
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L2820/00Details on specific features characterising valve gear arrangements
    • F01L2820/04Sensors
    • F01L2820/041Camshafts position or phase sensors
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02DCONTROLLING COMBUSTION ENGINES
    • F02D41/00Electrical control of supply of combustible mixture or its constituents
    • F02D41/0002Controlling intake air
    • F02D2041/001Controlling intake air for engines with variable valve actuation
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02DCONTROLLING COMBUSTION ENGINES
    • F02D41/00Electrical control of supply of combustible mixture or its constituents
    • F02D41/20Output circuits, e.g. for controlling currents in command coils
    • F02D2041/202Output circuits, e.g. for controlling currents in command coils characterised by the control of the circuit
    • F02D2041/2024Output circuits, e.g. for controlling currents in command coils characterised by the control of the circuit the control switching a load after time-on and time-off pulses
    • F02D2041/2027Control of the current by pulse width modulation or duty cycle control
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02DCONTROLLING COMBUSTION ENGINES
    • F02D41/00Electrical control of supply of combustible mixture or its constituents
    • F02D41/20Output circuits, e.g. for controlling currents in command coils
    • F02D2041/202Output circuits, e.g. for controlling currents in command coils characterised by the control of the circuit
    • F02D2041/2055Output circuits, e.g. for controlling currents in command coils characterised by the control of the circuit with means for determining actual opening or closing time
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/10Internal combustion engine [ICE] based vehicles
    • Y02T10/12Improving ICE efficiencies

Definitions

  • the present invention relates to an apparatus and method for controlling a cam, wherein, when the cam maintains a holding state, the holding PWM (pulse width modulation) range, in which the PWM moves slightly such that linearity is not ensured, is calculated and then applied to the cam control.
  • PWM pulse width modulation
  • an intake valve and exhaust valve In order to trap air and fuel inside a cylinder and combust same, an intake valve and exhaust valve have to open and close at the right time and position, and the control of such an intake valve and exhaust valve is chiefly implemented by a method in which a PWM signal is applied to the engine oil and a solenoid valve.
  • a system for manipulating the advance/retardation of a cam using engine oil reacts sensitively to the pressure and temperature of the oil.
  • the responsiveness of the cam which has a major influence on engine performance, depends entirely on PWM control, and, in such instances, it can happen that responsiveness is lacking or permanent deviation from the target position occurs due to the PWM, which is set for each and every condition, being insufficient or excessive.
  • the root cause of this phenomenon is because the PWM diagram for controlling the cam is not perfectly linear and, in particular, there is a marked problem in the holding PWM region for maintaining the current position.
  • the abovementioned background art cannot necessarily be called prior art disclosed to the general public before the filing date of the present invention, as the background art is technical information possessed by the inventors in order to derive the present invention or acquired during the process of deriving the present invention.
  • Patent Document 1 Korean Unexamined Patent Publication KR 2014-0111615 A
  • the present invention has been conceived in order to solve the abovementioned problems and/or limitations.
  • the objective of the present invention is to improve engine performance on the basis of correct responsiveness by accurately calculating the PWM required when changing the cam position; wherein, when the cam maintains a holding state, the holding PWM (pulse width modulation) range, in which the PWM moves slightly such that linearity is not ensured, is calculated and then applied to the cam control.
  • a cam control method is a method for controlling a cam by means of an ECU (electronic control unit) and may comprise the steps of: learning a holding region in which linearity is not ensured by performing an operation of increasing or decreasing a PWM signal when the cam maintains a holding state; and based on the results of the learning, generating a final PWM signal, which is a sum of a minimum PWM signal for the cam to leave the holding region and a control PWM signal for the cam to reach a desired position, and outputting the final PWM signal to an oil control valve.
  • the method may further comprise the step of the ECU starting the learning when the cam operates normally, by detecting a phase of the cam received from a cam position sensor.
  • the learning step may comprise the steps of: increasing the PWM signal if the cam is positioned in a target area; halting the increase of the PWM signal the instant a position of the cam changes whilst increasing the PWM signal, and storing the PWM signal, the increase of which has been halted, as a holding advance region for corresponding engine conditions; decreasing the PWM signal in the holding advance region; halting the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, and storing the PWM signal, the decrease of which has been halted, as a holding retard region for corresponding engine conditions; and defining an average of the PWM signal in the holding advance region and the PWM signal in the holding retard region as a learned value of the holding region.
  • the step of storing the PWM signal as a holding advance region may comprise the steps of : halting the increase of the PWM signal the instant the position of the cam changes whilst increasing the PWM signal, in order to stop a movement of the cam; decreasing the PWM signal by a certain amount in order to maintain a holding of the cam; and storing the PWM signal, which has been decreased by the certain amount, as the holding advance region for the corresponding engine conditions.
  • the step of storing the PWM signal as a holding retard region may comprise the steps of : halting the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, in order to stop a movement of the cam; increasing the PWM signal by a certain amount in order to maintain a holding of the cam; and storing the PWM signal, which has been increased by the certain amount, as the holding retard region for the corresponding engine conditions.
  • An apparatus for controlling a cam is an apparatus for controlling a cam by means of an ECU (electronic control unit) , and may comprise a learning unit for learning a holding region in which linearity is not ensured by performing an operation of increasing or decreasing a PWM signal when the cam maintains a holding state; and a control unit which, based on results of the learning, generates a final PWM signal, which is a sum of a minimum PWM signal for the cam to leave the holding region and a control PWM signal for the cam to reach a desired position, and outputs the final PWM signal to an oil control valve.
  • ECU electronic control unit
  • the apparatus further comprises a cam position sensor for detecting a phase of the cam, and the learning unit may start learning when the cam operates normally by detecting the phase of the cam received from the cam position sensor.
  • the learning unit may increase the PWM signal if the cam is positioned in a target area; halt the increase of the PWM signal the instant a position of the cam changes whilst increasing the PWM signal, and store the PWM signal, the increase of which has been halted, as a holding advance region for corresponding engine conditions; decrease the PWM signal in the holding advance region; halt the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, and store the PWM signal, the decrease of which has been halted, as a holding retard region for corresponding engine conditions; and define an average of the PWM signal in the holding advance region and the PWM signal in the holding retard region as a learned value of the holding region.
  • the learning unit may, during the storing as the holding advance region, halt the increase of the PWM signal the instant the position of the cam changes whilst increasing the PWM signal, in order to stop a movement of the cam; decreases the PWM signal by a certain amount in order to maintain the holding of the cam; and store the PWM signal, which has been decreased by the certain amount, as the holding advance region for the corresponding engine conditions.
  • the learning unit may, during the storing as the holding retard region, halt the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, in order to stop a movement of the cam; increases the PWM signal by a certain amount in order to maintain a holding of the cam; and store the PWM signal, which has been increased by the certain amount, as the holding retard region for the corresponding engine conditions .
  • the embodiments it is possible to improve engine performance on the basis of correct responsiveness by accurately calculating the PWM required when changing the cam position; wherein, when the cam maintains a holding state, the holding PWM range, in which the PWM moves slightly such that linearity is not ensured, is calculated and then applied to the cam control.
  • FIG. 1 is a drawing which has been drawn to describe, in general terms, the cam control apparatus according to an embodiment of the present invention.
  • FIG. 2 is a drawing which has been drawn to describe, in general terms, the holding region of the cam control apparatus of FIG.
  • FIG. 3 is a flowchart for explaining the cam control method according to an embodiment of the present invention.
  • an ECU refers to an electronic control unit. It is to be appreciated that the electronic control unit includes an engine control unit.
  • FIG. 1 is a drawing which has been drawn to describe, in general terms, the cam control apparatus according to an embodiment of the present invention
  • FIG. 2 is a drawing which has been drawn to describe, in general terms, the holding region of the cam control apparatus of FIG. 1.
  • the cam control apparatus may comprise: an oil control valve (110); a hydraulic circuit (120); a cam (130); a lock pin (140) ; an ECU (200) ; and a cam position sensor (300) .
  • the oil control valve (OCV) (110) can play the role of changing the direction of a fluid passage along which engine oil, which is supplied from an oil pump (not shown) goes to a variable valve timing unit (WT) upon receiving control from the ECU (200), thereby controlling the valve opening/closing times.
  • WT variable valve timing unit
  • Oil passage control with respect to the hydraulic circuit (120) can be achieved by connecting the hydraulic circuit (120), which is joined to the cam (130) that controls the intake valve and exhaust valve to the oil control valve (110), and by providing the lock pin (140), which fixes the cam (130) in the most retarded and most advanced operating positions, on the hydraulic circuit (120) , such that the position of a spool (or plunger) of the oil control valve (110) is moved by a PWM duty signal output from the ECU (200) .
  • the ECU (200) applies the PWM signal to the oil control valve (100)
  • the position of the spool (or plunger) of the oil control valve (110) moves to a target position, at which time, the position of the cam (130) can be controlled to be a parking (or detent) , retard, holding, or advance position in accordance with the hydraulic circuit (120) of the oil.
  • the hydraulic circuit (120) is changed and at the same time operation of the WT unit can take place.
  • the responsiveness of the cam (130) depends entirely on control of the PWM signal, and, in such instances, it can happen that responsiveness is lacking or permanent deviation from the target position occurs due to the PWM signal, which has been set for each and every condition, being insufficient or excessive.
  • the root cause of this phenomenon is because the PWM diagram for controlling the cam (130) is not perfectly linear and, in particular, there is a marked problem in the holding PWM region for maintaining the current position.
  • engine performance is to be improved on the basis of correct responsiveness by accurately calculating the PWM required when changing the cam (130) position; wherein, when the cam (130) maintains a holding state, the holding PWM range, in which the PWM signal moves slightly such that linearity is not ensured, is calculated and then applied to the cam (130) control.
  • the ECU (200) which controls the cam (130) may comprise: a learning unit (210); and a control unit (220) .
  • the learning unit (210) can learn the holding region in which linearity is not ensured, by performing an operation of increasing or decreasing the PWM signal when the cam (130) maintains a holding state.
  • the cam position sensor (300) detects the phase of the cam (130) so as to transmit a corresponding signal to the learning unit (210) when the cam (130) operates normally, and, when the cam (130) operates normally, the learning unit (210) can start learning.
  • the learning unit (210) can increase the PWM signal if the cam (130) is maintained in the holding state and is at the same time positioned in a target area.
  • increasing the PWM signal may include increasing a high region in a PWM signal comprising a high region and a low region.
  • the learning unit (210) can halt the increase of the PWM signal the instant the position of the cam (130) changes whilst increasing the PWM signal, which is to say, the instant the position of the cam (130) leaves a pre-set target (holding advance edge in FIG. 2) , in order to stop the movement of the cam (130), and can decrease the PWM signal by a certain amount in order to maintain the holding of the cam (130), and then can store the PWM signal, which has been decreased by the certain amount, as a holding advance region for corresponding engine conditions .
  • the learning unit (210) may decrease the PWM signal for the holding advance region.
  • decreasing the PWM signal may include decreasing a high region in a PWM signal comprising said high region and a low region.
  • the learning unit (210) can halt the decrease of the PWM signal the instant the position of the cam (130) changes whilst decreasing the PWM signal in a holding advance region, which is to say, the instant the position of the cam (130) leaves a pre set target (holding retard edge in FIG. 2) in order to stop the movement of the cam (130), and can increase the PWM signal by a certain amount in order to maintain the holding of the cam (130), and then can store the PWM signal, which has been increased by the certain amount, as a holding retard region for corresponding engine conditions.
  • the present embodiment has disclosed that the learning unit (210) proceeds in sequence from advance to retardation during holding region learning, but there is not necessarily any need to learn in the sequence from advance to retardation and it is also possible for learning to take place in a sequence from retardation to advance.
  • the learning unit (210) may define the average of the PWM signal in the holding advance region and the PWM signal in holding retard region as a learned value of the holding region.
  • the learned value of the holding region may comprise the PWM range of the holding region in which linearity is not ensured.
  • the control unit (220) can generate a final PWM signal, which is the sum of a minimum PWM signal for the cam (130) to leave the holding region and a control PWM signal for the cam (130) to reach a desired position, and can output same to an oil control valve (110) .
  • the PWM required when changing the position of the cam (130) can promote improvement of engine performance on the basis of quick responsiveness by accurately computing the PWM required when changing the position of the cam (130) as the sum of a minimum PWM signal for leaving the holding region and a control PWM signal for reaching a desired position.
  • FIG. 3 is a flowchart for explaining the cam control method according to an embodiment of the present invention.
  • description of those parts where the description with respect to FIG. 1 and FIG. 2 would be duplicated are omitted.
  • step S301 the ECU (200) receives a signal from the cam position sensor (300) so as to check whether the cam (130) operates normally.
  • step S303 the ECU (200) receives the phase of the cam (130) from the cam position sensor (300) so as to start learning when the cam operates normally.
  • step S305 the ECU (200) determines whether the position of the cam (130) is the target area when the cam (130) maintains a holding state.
  • step S307 when the position of the cam (130) is the target area, the ECU (200) increases the PWM signal so as to output same to the oil control valve (110) .
  • increasing the PWM signal may include increasing a high region in a PWM signal comprising said high region and a low region.
  • step S309 the ECU (200) determines whether the position of the cam (130) has left the pre-set target whilst increasing the PWM signal.
  • step S311 when the position of the cam (130) has left the pre-set target, the ECU (200) halts the increase of the PWM signal the instant the position of the cam (130) leaves the pre- set target, which is to say, the instant the position of the cam (130) changes, in order to stop the movement of the cam (130), and decreases the PWM signal by a certain amount in order to maintain the holding of the cam (130), and then stores the PWM signal, which has been decreased by the certain amount, as a holding advance region for corresponding engine conditions.
  • step S313 when storage of the PWM signal with respect to the holding advance region is completed, the ECU (200) decreases the PWM signal in the holding advance region.
  • decreasing the PWM signal may include decreasing a high region in a PWM signal comprising said high region and a low region.
  • step S315 the ECU (200) determines whether the position of the cam (130) has left the pre-set target whilst decreasing the PWM signal in the holding advance region.
  • step S317 when the position of the cam (130) has left the pre-set target, the ECU (200) halts the decrease of the PWM signal the instant the position of the cam (130) leaves the target, which is to say, the instant the position of the cam (130) changes in order to stop the movement of the cam (130) , and increases the PWM signal by a certain amount in order to maintain the holding of the cam (130), and then stores the PWM signal, which has been increased by a certain amount, as a holding retardation region for corresponding engine conditions.
  • step S319 the ECU (200) defines the average of the PWM signal in the holding advance region and the PWM signal in holding retard region as a learned value of the holding region.
  • step S321 the ECU (200) sets the final PWM signal, which is required when changing the position of the cam (130) subsequently to a value which is the sum of a minimum PWM signal for leaving the holding region and a control PWM signal for reaching a desired position.
  • the embodiment according to the present invention described above may be implemented in the form of a computer program which can be executed through various constituent elements in a computer, and such a computer program may be recorded on a computer-readable medium.
  • the medium may comprise hardware devices specially configured to store and execute program commands, including: magnetic media such as hard discs, floppy discs, and magnetic tapes; optical recording media such as CD-ROMs and DVDs; magneto-optical medium such as floptical discs; and ROM, RAM and flash memories.
  • the computer program may be one which is specifically designed and configured for the present invention or one which is available and well-known to a person skilled in the field of computer software.
  • Examples of the computer program can include machine language code such as that created by means of a compiler, as well as high-level language code which can be executed by means of a computer by using an interpreter or the like.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)
  • Valve Device For Special Equipments (AREA)

Abstract

The present invention relates to an apparatus and method for controlling a cam, wherein, when the cam maintains a holding state, the holding PWM (pulse width modulation) range, in which the PWM moves slightly such that linearity is not ensured, is calculated and then applied to the cam control. The cam control method according to an embodiment of the present invention is a method for controlling a cam by means of an ECU (electronic control unit) and may comprise the steps of: learning a holding region in which linearity is not ensured by performing an operation of increasing or decreasing a PWM signal when the cam maintains a holding state; and based on the results of the learning, generating a final PWM signal, which is a sum of a minimum PWM signal for the cam to leave the holding region and a control PWM signal for the cam to reach a desired position, and outputting the final PWM signal to an oil control valve.

Description

[Description of the Invention]
[Title of the Invention]
Apparatus and Method for Controlling Cam [Technical Field]
The present invention relates to an apparatus and method for controlling a cam, wherein, when the cam maintains a holding state, the holding PWM (pulse width modulation) range, in which the PWM moves slightly such that linearity is not ensured, is calculated and then applied to the cam control.
[Background Art of the Invention]
In order to trap air and fuel inside a cylinder and combust same, an intake valve and exhaust valve have to open and close at the right time and position, and the control of such an intake valve and exhaust valve is chiefly implemented by a method in which a PWM signal is applied to the engine oil and a solenoid valve.
A system for manipulating the advance/retardation of a cam using engine oil reacts sensitively to the pressure and temperature of the oil. During such control, the responsiveness of the cam, which has a major influence on engine performance, depends entirely on PWM control, and, in such instances, it can happen that responsiveness is lacking or permanent deviation from the target position occurs due to the PWM, which is set for each and every condition, being insufficient or excessive.
The root cause of this phenomenon is because the PWM diagram for controlling the cam is not perfectly linear and, in particular, there is a marked problem in the holding PWM region for maintaining the current position. The abovementioned background art cannot necessarily be called prior art disclosed to the general public before the filing date of the present invention, as the background art is technical information possessed by the inventors in order to derive the present invention or acquired during the process of deriving the present invention.
[Prior Art Documents]
[Patent Documents]
(Patent Document 1) Korean Unexamined Patent Publication KR 2014-0111615 A
[Details of the Invention]
[Problem to be Solved]
The present invention has been conceived in order to solve the abovementioned problems and/or limitations. In one aspect, the objective of the present invention is to improve engine performance on the basis of correct responsiveness by accurately calculating the PWM required when changing the cam position; wherein, when the cam maintains a holding state, the holding PWM (pulse width modulation) range, in which the PWM moves slightly such that linearity is not ensured, is calculated and then applied to the cam control.
[Means of Solving the Problem]
A cam control method according to an embodiment of the present invention is a method for controlling a cam by means of an ECU (electronic control unit) and may comprise the steps of: learning a holding region in which linearity is not ensured by performing an operation of increasing or decreasing a PWM signal when the cam maintains a holding state; and based on the results of the learning, generating a final PWM signal, which is a sum of a minimum PWM signal for the cam to leave the holding region and a control PWM signal for the cam to reach a desired position, and outputting the final PWM signal to an oil control valve.
The method may further comprise the step of the ECU starting the learning when the cam operates normally, by detecting a phase of the cam received from a cam position sensor.
The learning step may comprise the steps of: increasing the PWM signal if the cam is positioned in a target area; halting the increase of the PWM signal the instant a position of the cam changes whilst increasing the PWM signal, and storing the PWM signal, the increase of which has been halted, as a holding advance region for corresponding engine conditions; decreasing the PWM signal in the holding advance region; halting the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, and storing the PWM signal, the decrease of which has been halted, as a holding retard region for corresponding engine conditions; and defining an average of the PWM signal in the holding advance region and the PWM signal in the holding retard region as a learned value of the holding region.
The step of storing the PWM signal as a holding advance region may comprise the steps of : halting the increase of the PWM signal the instant the position of the cam changes whilst increasing the PWM signal, in order to stop a movement of the cam; decreasing the PWM signal by a certain amount in order to maintain a holding of the cam; and storing the PWM signal, which has been decreased by the certain amount, as the holding advance region for the corresponding engine conditions.
The step of storing the PWM signal as a holding retard region may comprise the steps of : halting the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, in order to stop a movement of the cam; increasing the PWM signal by a certain amount in order to maintain a holding of the cam; and storing the PWM signal, which has been increased by the certain amount, as the holding retard region for the corresponding engine conditions.
An apparatus for controlling a cam according to an embodiment of the present invention is an apparatus for controlling a cam by means of an ECU (electronic control unit) , and may comprise a learning unit for learning a holding region in which linearity is not ensured by performing an operation of increasing or decreasing a PWM signal when the cam maintains a holding state; and a control unit which, based on results of the learning, generates a final PWM signal, which is a sum of a minimum PWM signal for the cam to leave the holding region and a control PWM signal for the cam to reach a desired position, and outputs the final PWM signal to an oil control valve.
The apparatus further comprises a cam position sensor for detecting a phase of the cam, and the learning unit may start learning when the cam operates normally by detecting the phase of the cam received from the cam position sensor.
The learning unit may increase the PWM signal if the cam is positioned in a target area; halt the increase of the PWM signal the instant a position of the cam changes whilst increasing the PWM signal, and store the PWM signal, the increase of which has been halted, as a holding advance region for corresponding engine conditions; decrease the PWM signal in the holding advance region; halt the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, and store the PWM signal, the decrease of which has been halted, as a holding retard region for corresponding engine conditions; and define an average of the PWM signal in the holding advance region and the PWM signal in the holding retard region as a learned value of the holding region. The learning unit may, during the storing as the holding advance region, halt the increase of the PWM signal the instant the position of the cam changes whilst increasing the PWM signal, in order to stop a movement of the cam; decreases the PWM signal by a certain amount in order to maintain the holding of the cam; and store the PWM signal, which has been decreased by the certain amount, as the holding advance region for the corresponding engine conditions.
The learning unit may, during the storing as the holding retard region, halt the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, in order to stop a movement of the cam; increases the PWM signal by a certain amount in order to maintain a holding of the cam; and store the PWM signal, which has been increased by the certain amount, as the holding retard region for the corresponding engine conditions .
As well as the above, other methods, other systems and a computer program for executing the method for realizing the present invention may be further provided.
Other aspects, features, and advantages aside from the ones mentioned above are made clear in the drawings, claims and detailed description of the Invention below.
[Advantages of the Invention]
According to the embodiments, it is possible to improve engine performance on the basis of correct responsiveness by accurately calculating the PWM required when changing the cam position; wherein, when the cam maintains a holding state, the holding PWM range, in which the PWM moves slightly such that linearity is not ensured, is calculated and then applied to the cam control. The advantages of the present invention are not limited to those mentioned above, and other unmentioned advantages should be clearly understandable to a person skilled in the art from the disclosure below.
[Brief Description of the Drawings]
FIG. 1 is a drawing which has been drawn to describe, in general terms, the cam control apparatus according to an embodiment of the present invention.
FIG. 2 is a drawing which has been drawn to describe, in general terms, the holding region of the cam control apparatus of FIG.
1.
FIG. 3 is a flowchart for explaining the cam control method according to an embodiment of the present invention.
[Detailed Disclosure for Implementing the Invention]
The advantages and features of the present invention and method for achieving same will be made clear with reference to the accompanying drawings together with the embodiments described in detail. However, the present invention is not limited to the embodiments set forth below and may be realised in various different forms, and should be understood to include all modifications, equivalents and substitutions which are included in the concept and technical scope of the present invention. The embodiments set forth below are provided to fully disclose the present invention and to allow a person skilled in the technical field to which the present invention belongs to be fully aware of the scope of the invention. In the description of the present invention, when it is considered that the detailed description of related well-known features may obfuscate key features of the present invention, detailed description thereof has been omitted
Terms used in the present application are merely used to describe specific embodiments and are not intended to limit the present invention. Singular expressions encompass singular and plural expressions unless made evident otherwise from context. In the present application, terms such as "comprising" or "having" are intended to indicate the presence of a feature, number, step, operation, constituent element, component or combination thereof mentioned in the specification, and should be understood to not exclude the presence, or the ability to add, one or more other features or numbers, steps, operations, constituent elements, components or combinations thereof. Terms such as first and second may be used to describe various constituent elements, but these constituent elements are not to be limited by such terms. These terms are used only to differentiate one constituent element from another constituent element.
Hereinbelow, embodiments according to the present invention are described in detail with reference to the accompanying drawings, and, in the description with reference to the accompanying drawings, the same or corresponding constituent elements have the same figure reference numeral, and duplicate descriptions of same are omitted.
Throughout the description, an ECU refers to an electronic control unit. It is to be appreciated that the electronic control unit includes an engine control unit.
FIG. 1 is a drawing which has been drawn to describe, in general terms, the cam control apparatus according to an embodiment of the present invention, and FIG. 2 is a drawing which has been drawn to describe, in general terms, the holding region of the cam control apparatus of FIG. 1. With reference to FIG. 1 and FIG. 2, the cam control apparatus may comprise: an oil control valve (110); a hydraulic circuit (120); a cam (130); a lock pin (140) ; an ECU (200) ; and a cam position sensor (300) .
The oil control valve (OCV) (110) can play the role of changing the direction of a fluid passage along which engine oil, which is supplied from an oil pump (not shown) goes to a variable valve timing unit (WT) upon receiving control from the ECU (200), thereby controlling the valve opening/closing times. Oil passage control with respect to the hydraulic circuit (120) can be achieved by connecting the hydraulic circuit (120), which is joined to the cam (130) that controls the intake valve and exhaust valve to the oil control valve (110), and by providing the lock pin (140), which fixes the cam (130) in the most retarded and most advanced operating positions, on the hydraulic circuit (120) , such that the position of a spool (or plunger) of the oil control valve (110) is moved by a PWM duty signal output from the ECU (200) .
When the ECU (200) applies the PWM signal to the oil control valve (100) , the position of the spool (or plunger) of the oil control valve (110) moves to a target position, at which time, the position of the cam (130) can be controlled to be a parking (or detent) , retard, holding, or advance position in accordance with the hydraulic circuit (120) of the oil. This is to say, depending on the position of the spool (or plunger) of the oil control valve (110), the hydraulic circuit (120) is changed and at the same time operation of the WT unit can take place.
Here, the responsiveness of the cam (130) depends entirely on control of the PWM signal, and, in such instances, it can happen that responsiveness is lacking or permanent deviation from the target position occurs due to the PWM signal, which has been set for each and every condition, being insufficient or excessive. The root cause of this phenomenon is because the PWM diagram for controlling the cam (130) is not perfectly linear and, in particular, there is a marked problem in the holding PWM region for maintaining the current position.
Hence, in the present embodiments, engine performance is to be improved on the basis of correct responsiveness by accurately calculating the PWM required when changing the cam (130) position; wherein, when the cam (130) maintains a holding state, the holding PWM range, in which the PWM signal moves slightly such that linearity is not ensured, is calculated and then applied to the cam (130) control.
In the present embodiment, the ECU (200) which controls the cam (130) may comprise: a learning unit (210); and a control unit (220) .
The learning unit (210) can learn the holding region in which linearity is not ensured, by performing an operation of increasing or decreasing the PWM signal when the cam (130) maintains a holding state. Here, the cam position sensor (300) detects the phase of the cam (130) so as to transmit a corresponding signal to the learning unit (210) when the cam (130) operates normally, and, when the cam (130) operates normally, the learning unit (210) can start learning.
The learning unit (210) can increase the PWM signal if the cam (130) is maintained in the holding state and is at the same time positioned in a target area. Here, increasing the PWM signal may include increasing a high region in a PWM signal comprising a high region and a low region.
The learning unit (210) can halt the increase of the PWM signal the instant the position of the cam (130) changes whilst increasing the PWM signal, which is to say, the instant the position of the cam (130) leaves a pre-set target (holding advance edge in FIG. 2) , in order to stop the movement of the cam (130), and can decrease the PWM signal by a certain amount in order to maintain the holding of the cam (130), and then can store the PWM signal, which has been decreased by the certain amount, as a holding advance region for corresponding engine conditions . When storage of the PWM signal for the holding advance region is completed, the learning unit (210) may decrease the PWM signal for the holding advance region. Here, decreasing the PWM signal may include decreasing a high region in a PWM signal comprising said high region and a low region.
The learning unit (210) can halt the decrease of the PWM signal the instant the position of the cam (130) changes whilst decreasing the PWM signal in a holding advance region, which is to say, the instant the position of the cam (130) leaves a pre set target (holding retard edge in FIG. 2) in order to stop the movement of the cam (130), and can increase the PWM signal by a certain amount in order to maintain the holding of the cam (130), and then can store the PWM signal, which has been increased by the certain amount, as a holding retard region for corresponding engine conditions.
For convenience of explanation, the present embodiment has disclosed that the learning unit (210) proceeds in sequence from advance to retardation during holding region learning, but there is not necessarily any need to learn in the sequence from advance to retardation and it is also possible for learning to take place in a sequence from retardation to advance.
The learning unit (210) may define the average of the PWM signal in the holding advance region and the PWM signal in holding retard region as a learned value of the holding region. Here, the learned value of the holding region may comprise the PWM range of the holding region in which linearity is not ensured. Based on the results of learning of the learning unit (210), the control unit (220) can generate a final PWM signal, which is the sum of a minimum PWM signal for the cam (130) to leave the holding region and a control PWM signal for the cam (130) to reach a desired position, and can output same to an oil control valve (110) . Accordingly, the PWM required when changing the position of the cam (130) can promote improvement of engine performance on the basis of quick responsiveness by accurately computing the PWM required when changing the position of the cam (130) as the sum of a minimum PWM signal for leaving the holding region and a control PWM signal for reaching a desired position.
FIG. 3 is a flowchart for explaining the cam control method according to an embodiment of the present invention. In the description below, description of those parts where the description with respect to FIG. 1 and FIG. 2 would be duplicated are omitted.
Referring to FIG. 3, in step S301, the ECU (200) receives a signal from the cam position sensor (300) so as to check whether the cam (130) operates normally.
In step S303, the ECU (200) receives the phase of the cam (130) from the cam position sensor (300) so as to start learning when the cam operates normally.
In step S305, the ECU (200) determines whether the position of the cam (130) is the target area when the cam (130) maintains a holding state.
In step S307, when the position of the cam (130) is the target area, the ECU (200) increases the PWM signal so as to output same to the oil control valve (110) . Here, increasing the PWM signal may include increasing a high region in a PWM signal comprising said high region and a low region.
In step S309, the ECU (200) determines whether the position of the cam (130) has left the pre-set target whilst increasing the PWM signal.
In step S311, when the position of the cam (130) has left the pre-set target, the ECU (200) halts the increase of the PWM signal the instant the position of the cam (130) leaves the pre- set target, which is to say, the instant the position of the cam (130) changes, in order to stop the movement of the cam (130), and decreases the PWM signal by a certain amount in order to maintain the holding of the cam (130), and then stores the PWM signal, which has been decreased by the certain amount, as a holding advance region for corresponding engine conditions.
In step S313, when storage of the PWM signal with respect to the holding advance region is completed, the ECU (200) decreases the PWM signal in the holding advance region. Here, decreasing the PWM signal may include decreasing a high region in a PWM signal comprising said high region and a low region.
In step S315, the ECU (200) determines whether the position of the cam (130) has left the pre-set target whilst decreasing the PWM signal in the holding advance region.
In step S317, when the position of the cam (130) has left the pre-set target, the ECU (200) halts the decrease of the PWM signal the instant the position of the cam (130) leaves the target, which is to say, the instant the position of the cam (130) changes in order to stop the movement of the cam (130) , and increases the PWM signal by a certain amount in order to maintain the holding of the cam (130), and then stores the PWM signal, which has been increased by a certain amount, as a holding retardation region for corresponding engine conditions.
In step S319, the ECU (200) defines the average of the PWM signal in the holding advance region and the PWM signal in holding retard region as a learned value of the holding region.
In step S321, the ECU (200) sets the final PWM signal, which is required when changing the position of the cam (130) subsequently to a value which is the sum of a minimum PWM signal for leaving the holding region and a control PWM signal for reaching a desired position. The embodiment according to the present invention described above may be implemented in the form of a computer program which can be executed through various constituent elements in a computer, and such a computer program may be recorded on a computer-readable medium. In such a case, the medium may comprise hardware devices specially configured to store and execute program commands, including: magnetic media such as hard discs, floppy discs, and magnetic tapes; optical recording media such as CD-ROMs and DVDs; magneto-optical medium such as floptical discs; and ROM, RAM and flash memories.
Meanwhile, the computer program may be one which is specifically designed and configured for the present invention or one which is available and well-known to a person skilled in the field of computer software. Examples of the computer program can include machine language code such as that created by means of a compiler, as well as high-level language code which can be executed by means of a computer by using an interpreter or the like.
In the specification of the present invention (in particular in the claims) the use of the word "the" and similar demonstrative wording may entail both the singular and the plural. Furthermore, when a range is mentioned in the present invention, this includes any invention in which individual values belonging to the range have been applied (unless there is a statement to the contrary) , and this is the same as for statements of individual values constituting ranges in the detailed description of the invention. With respect to the steps which constitute the method according to the present invention, said steps may be performed in any appropriate order unless the order is clearly stated or there is a statement to the contrary. In all events, the present invention is not limited by the disclosed order of the steps. The use of all the embodiments or illustrative wording (for example, etc.) in the present invention is simply in order to describe the present invention in detail, but the scope of the present invention is not limited by the above embodiments or illustrative wordings since they are not delimited by the claims. Furthermore, a person skilled in the art will be able to understand that various amendments, combinations and modifications can be implemented in accordance with design conditions and other factors within scope of the attached claims or equivalents thereof .
Accordingly, the concept of the present invention is not defined so as to be limited to the described embodiments; and the scope of the concept of the present invention encompasses not only the claims below but also an entire scope in which changes equal to the claims or equivalently modified therefrom are made.
[Description of the Reference Numerals]
110: Oil control valve
120: Hydraulic circuit
130: Cam
140 : Lock pin
200: ECU
210: Learning unit
220: Control unit
300: Cam position sensor

Claims

[Claims ]
[Claim 1]
A method for controlling a cam by means of an ECU (electronic control unit) comprising the steps of:
learning a holding region in which linearity is not ensured by performing an operation of increasing or decreasing a PWM signal when the cam maintains a holding state; and
based on the results of the learning, generating a final PWM signal, which is a sum of a minimum PWM signal for the cam to leave the holding region and a control PWM signal for the cam to reach a desired position, and outputting the final PWM signal to an oil control valve.
[Claim 2]
The method for controlling a cam according to Claim 1,
further comprising the step of the ECU starting the learning when the cam operates normally, by detecting a phase of the cam received from a cam position sensor.
[Claim 3]
The method for controlling a cam according to Claim 1, wherein the learning step comprises the steps of:
increasing the PWM signal if the cam is positioned in a target area;
halting the increase of the PWM signal the instant a position of the cam changes whilst increasing the PWM signal, and storing the PWM signal, the increase of which has been halted, as a holding advance region for corresponding engine conditions; decreasing the PWM signal in the holding advance region;
halting the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, and storing the PWM signal, the decrease of which has been halted, as a holding retard region for corresponding engine conditions; and defining an average of the PWM signal in the holding advance region and the PWM signal in the holding retard region as a learned value of the holding region.
[Claim 4]
A method for controlling a cam according to Claim 3, wherein the step of storing the PWM signal as a holding advance region comprises the steps of:
halting the increase of the PWM signal the instant the position of the cam changes whilst increasing the PWM signal, in order to stop a movement of the cam;
decreasing the PWM signal by a certain amount in order to maintain a holding of the cam; and
storing the PWM signal, which has been decreased by the certain amount, as the holding advance region for the corresponding engine conditions.
[Claim 5]
A method for controlling a cam according to Claim 3, wherein the step of storing the PWM signal as a holding retard region comprises the steps of:
halting the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, in order to stop a movement of the cam;
increasing the PWM signal by a certain amount in order to maintain a holding of the cam; and
storing the PWM signal, which has been increased by the certain amount, as the holding retard region for the corresponding engine conditions .
[Claim 6]
An apparatus for controlling a cam by means of an ECU (electronic control unit), the apparatus comprising:
a learning unit for learning a holding region in which linearity is not ensured by performing an operation of increasing or decreasing a PWM signal when the cam maintains a holding state; and
a control unit which, based on results of the learning, generates a final PWM signal, which is a sum of a minimum PWM signal for the cam to leave the holding region and a control PWM signal for the cam to reach a desired position, and outputs the final PWM signal to an oil control valve.
[Claim 7]
The apparatus for controlling a cam according to Claim 6, further comprising :
a cam position sensor for detecting a phase of the cam, wherein the learning unit starts learning when the cam operates normally by detecting the phase of the cam received from the cam position sensor.
[Claim 8]
The apparatus for controlling a cam according to Claim 6, wherein the learning unit:
increases the PWM signal if the cam is positioned in a target area;
halts the increase of the PWM signal the instant a position of the cam changes whilst increasing the PWM signal, and stores the PWM signal, the increase of which has been halted, as a holding advance region for corresponding engine conditions;
decreases the PWM signal in the holding advance region;
halts the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, and stores the PWM signal, the decrease of which has been halted, as a holding retard region for corresponding engine conditions; and
defines an average of the PWM signal in the holding advance region and the PWM signal in the holding retard region as a learned value of the holding region.
[Claim 9]
The apparatus for controlling a cam according to Claim 8, wherein the learning unit:
during the storing as the holding advance region, halts the increase of the PWM signal the instant the position of the cam changes whilst increasing the PWM signal, in order to stop a movement of the cam; decreases the PWM signal by a certain amount in order to maintain the holding of the cam; and stores the PWM signal, which has been decreased by the certain amount, as the holding advance region for the corresponding engine conditions.
[Claim 10]
The apparatus for controlling a cam according to Claim 8, wherein the learning unit:
during the storing as the holding retard region, halts the decrease of the PWM signal the instant the position of the cam changes whilst decreasing the PWM signal, in order to stop a movement of the cam; increases the PWM signal by a certain amount in order to maintain a holding of the cam; and stores the PWM signal, which has been increased by the certain amount, as the holding retard region for the corresponding engine conditions.
PCT/EP2020/050008 2019-01-04 2020-01-02 Apparatus and method for controlling cam Ceased WO2020141189A1 (en)

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DE112020000316.7T DE112020000316T5 (en) 2019-01-04 2020-01-02 Cam control apparatus and method
US17/420,777 US12110814B2 (en) 2019-01-04 2020-01-02 Apparatus and method for controlling a cam

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5562071A (en) * 1994-08-31 1996-10-08 Nippondenso Co., Ltd. Engine valve operation timing control apparatus
US20030000489A1 (en) * 2001-06-15 2003-01-02 Yoshihiro Majima Control apparatus for device having dead band, and variable valve system
US20070266976A1 (en) * 2006-05-19 2007-11-22 Denso Corporation Controller for vane-type variable valve timing adjusting mechanism
US20090151671A1 (en) * 2006-04-26 2009-06-18 Denso Corporation Controller for vane-type variable timing adjusting mechanism
KR20140111615A (en) 2013-03-11 2014-09-19 휴스코 오토모티브 홀딩스 엘엘씨 System for varying cylinder valve timing in an internal combustion engine

Family Cites Families (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE513062C2 (en) 1992-06-30 2000-06-26 Fanja Ltd Procedure for controlling the operation of a combustion piston engine and engine for carrying out the procedure
JPH0914457A (en) 1995-07-03 1997-01-14 Sony Corp Motor assembly and bearing device
JP3546700B2 (en) 1998-05-12 2004-07-28 トヨタ自動車株式会社 Valve timing control device for internal combustion engine
JP3701519B2 (en) * 1999-08-13 2005-09-28 株式会社日立製作所 Engine control device
JP2001254638A (en) * 2000-03-10 2001-09-21 Honda Motor Co Ltd Valve timing control device for internal combustion engine
JP3982988B2 (en) 2000-11-02 2007-09-26 株式会社日立製作所 Control device for electromagnetic variable valve timing device
US6792902B2 (en) 2002-04-22 2004-09-21 Borgwarner Inc. Externally mounted DPCS (differential pressure control system) with position sensor control to reduce frictional and magnetic hysteresis
JP4353249B2 (en) * 2007-01-19 2009-10-28 トヨタ自動車株式会社 Hydraulic actuator controller
JP4342562B2 (en) 2007-02-02 2009-10-14 三菱電機株式会社 Internal combustion engine control device
JP4830998B2 (en) * 2007-07-17 2011-12-07 株式会社デンソー Valve characteristic control device and valve characteristic control system
JP2009138650A (en) * 2007-12-07 2009-06-25 Denso Corp Variable valve timing control device for internal combustion engine
JP4978542B2 (en) * 2008-04-17 2012-07-18 株式会社デンソー Valve timing control device and valve timing control system
KR100999619B1 (en) * 2008-05-14 2010-12-08 현대자동차주식회사 Engine oil monitoring device
DE102014209327B4 (en) 2014-05-16 2021-01-07 Vitesco Technologies GmbH Method for adjusting an actuator for a camshaft of an internal combustion engine
KR101558392B1 (en) * 2014-06-09 2015-10-07 현대자동차 주식회사 Control system of variable valve timing device
KR101567226B1 (en) * 2014-06-25 2015-11-06 현대자동차주식회사 Method for Improving Response of Middle Phase type Continuously Variable Valve Timing System
US9410453B2 (en) 2014-10-21 2016-08-09 Ford Global Technologies, Llc Method and system for variable cam timing device
KR101646386B1 (en) * 2014-11-25 2016-08-16 현대자동차주식회사 Method and system for deecting malfunction of fastening bolt in cvvt
KR101575304B1 (en) * 2014-12-02 2015-12-07 현대자동차 주식회사 Method and system for controlling continuously variable valve timing
JP6780573B2 (en) * 2017-04-21 2020-11-04 株式会社デンソー Valve timing adjuster

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5562071A (en) * 1994-08-31 1996-10-08 Nippondenso Co., Ltd. Engine valve operation timing control apparatus
US20030000489A1 (en) * 2001-06-15 2003-01-02 Yoshihiro Majima Control apparatus for device having dead band, and variable valve system
US20090151671A1 (en) * 2006-04-26 2009-06-18 Denso Corporation Controller for vane-type variable timing adjusting mechanism
US20070266976A1 (en) * 2006-05-19 2007-11-22 Denso Corporation Controller for vane-type variable valve timing adjusting mechanism
KR20140111615A (en) 2013-03-11 2014-09-19 휴스코 오토모티브 홀딩스 엘엘씨 System for varying cylinder valve timing in an internal combustion engine

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US20220065141A1 (en) 2022-03-03
CN113227562B (en) 2023-12-12
KR101992795B1 (en) 2019-06-25
CN113227562A (en) 2021-08-06
DE112020000316T5 (en) 2021-10-07
US12110814B2 (en) 2024-10-08

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