Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
  • F02D9/08—Throttle valves specially adapted therefor; Arrangements of such valves in conduits
  • F02D9/12—Throttle valves specially adapted therefor; Arrangements of such valves in conduits having slidably-mounted valve members; having valve members movable longitudinally of conduit
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D11/00—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated
  • F02D11/04—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated characterised by mechanical control linkages
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D11/00—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated
  • F02D11/06—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated characterised by non-mechanical control linkages, e.g. fluid control linkages or by control linkages with power drive or assistance
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D11/00—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated
  • F02D11/06—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated characterised by non-mechanical control linkages, e.g. fluid control linkages or by control linkages with power drive or assistance
  • F02D11/10—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated characterised by non-mechanical control linkages, e.g. fluid control linkages or by control linkages with power drive or assistance of the electric type
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D11/00—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated
  • F02D11/06—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated characterised by non-mechanical control linkages, e.g. fluid control linkages or by control linkages with power drive or assistance
  • F02D11/10—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated characterised by non-mechanical control linkages, e.g. fluid control linkages or by control linkages with power drive or assistance of the electric type
  • F02D11/105—Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated characterised by non-mechanical control linkages, e.g. fluid control linkages or by control linkages with power drive or assistance of the electric type characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/52—Systems for actuating EGR valves
  • F02M26/53—Systems for actuating EGR valves using electric actuators, e.g. solenoids
  • F02M26/54—Rotary actuators, e.g. step motors

Definitions

• the invention relates to the field of motor vehicles. It relates more particularly to an engine control valve provided to manage the circulation of a fluid in a duct connected to the engine of the vehicle.
• Motor control valves actuated by a rotary motor are known and adapted to move in translation a valve disposed in a conduit and for controlling the passage of fluid in this conduit.
• These valves comprise an electric motor associated with a gear train for rotating a cam system. The displacement in translation generated allows the drive of the valve in a rectilinear motion.
• the purpose of the invention is to improve this type of valve by proposing a motor control valve whose control is easier and more robust.
• the invention provides an engine control valve comprising a rotary actuator, a valve, and a device for transforming movement adapted to transform the rotation of the actuator in translation of the valve, characterized in that the device motion transformation comprises a constant pitch helical link for translational drive of the valve.
• the translation drive of the valve by the motion transformation device is made according to a substantially linear law, that is to say that the axial force exerted on the valve for its opening undergoes variations, depending on the valve lift and therefore the rotation of the actuator, which can be represented by a substantially straight line.
• This does not allow to obtain a significant reduction in the force applied to the valve from the beginning of the valve lift phase (where the efforts to overcome are the most important), as commonly practiced in the valves of the art prior art in which force decreases rapidly after the beginning of emergence (see Figure 4, dashed curve), according to a link whose pitch is not constant or has a double slope.
• the valve according to the invention has for its part a transformation device with linear behavior and therefore with improved controllability.
• This valve may further comprise the following characteristics, alone or in combination: the helical linkage comprises a cam path whose pitch is constant;
• the movement transformation device comprises a tubular wall in which the cam path is made
• the cam path comprises two tracks arranged facing each other on the tubular wall;
• the valve comprises at least one roller attached to the valve and adapted to cooperate with the cam path;
• At least one roller is rotatably mounted on a bar attached to the valve, the bar being disposed in the volume defined by the tubular wall so as to cooperate with an input wheel which is driven by the rotary actuator and which is adapted to rotate the bar; the input wheel can be driven directly or indirectly by the rotary actuator;
• the input wheel is rotatably mounted on the tubular wall;
• the input wheel is rotatably mounted on the tubular wall by means of a bearing;
• a position sensor of the valve is disposed in the space delimited by the tubular wall
• the position sensor is a rectilinear displacement sensor;
• the use of a linear displacement sensor is more advantageous than a rotary sensor because it directly measures the displacement of the valve.
• This The sensor here has, in fact, a substantially linear behavior since it is directly associated with the element (the valve) whose position is to be determined, without reduction or transformation of movement.
• rotary sensors are generally used to determine the angular position of a cam acting on the valve and indirectly to deduce the position of the valve taking into account the shape of said cam.
• a rectilinear displacement sensor would in fact have a non-linear behavior.
• substantially linear behavior means that an element of the valve has a physical behavior close to a theoretical linear system model, in the sense that it is given in the fields of automation and processing of signal;
• the rotary actuator comprises an electric motor with a substantially linear behavior
• This motor is a DC motor;
• the rotary actuator is connected to the motion transformation device by transmission means having a substantially linear behavior;
• valve comprises means for returning the valve to the closed position, these biasing means having a substantially linear behavior
• the elastic return means comprise a helical torsion spring
• the kinematic chain running from the rotary actuator to the valve consists of elements exhibiting a substantially linear behavior;
• Another aspect of the invention is an assembly of such a valve and control means programmed according to a linear model.
• the control means may comprise conventional electronic devices such as a motor control unit ("Engine Control Unit” in English). They are programmed according to a linear model, that is to say that the transfer function of the model which describes the position of the valve as a function of the setpoint input is a linear function.
• FIG. 1 is a perspective view of a valve according to the invention.
• FIG. 2 is an exploded view of the valve of FIG. 1;
• FIG. 3 is a perspective view of the device for transforming movements of the valve of FIG. 1;
• FIG. 4 is a graph showing the axial force applied to the valve as a function of its lift stroke in the valve of FIG. 1.
• FIG. 1 shows an engine control valve 1 which is in the present example an exhaust gas recirculation valve commonly referred to as an "EGR valve".
• the various constituent elements of the valve 1 are visible separately in the exploded view of FIG. 2.
• the valve 1 comprises a fluid inlet 2 and a fluid outlet 3 between which the head 4 of a valve 5 is arranged.
• the valve 5 in the closed position to stop the flow of the fluid entering through the inlet 2 and out through the outlet 3.
• the full opening of the valve 5 allows the opposite free flow of the fluid while maintaining the valve 5 in an intermediate position allows the dosing of the fluid.
• the valve 1 comprises a support 6 on which is mounted an actuator, constituted here by an electric motor 7, a motion transformation device 9, and a transmission wheel 8 which allows the motor 7 to drive the motion transformation device 9, the latter transforming the rotary movement of the transmission wheel 8 in rectilinear motion of the valve 5.
• the movement transformation device 9 has a generally tubular shape and has at one of its ends a valve seat 10 and at the other end of its ends a cam path 11.
• the valve may be without a seat valve.
• the cam path 11 comprises two tracks made in a tubular wall 12 of the motion transformation device 9.
• a bar 13 fixed on the valve 5 and provided with rollers 14 is adapted to cooperate with the cam path 11
• the movement transformation device 9 cooperates with an input wheel 15 having a toothed portion 16 attached to a portion tubular 17 rotatably mounted on the motion transformation device 9 by means of a bearing 18.
• Elastic return means 19 are here provided in the form of a helical torsion spring for biasing the input wheel 15 in one of its extreme angular positions corresponding in this example to the closed position of the valve 5.
• the motor 7 is thus actuated against the return means 19 to open the valve 5.
• a position sensor 20 further allows the position of the valve 5 along its axial stroke to be measured at any time by means of a probe
• the sensor 20 has a linear behavior in that the probe 21
• a protective cover 22 (see FIG. 2) mounted on the support 6 protects the rotating elements of the valve 1.
• the motor 7 is powered and driven according to a control integrated in a conventional manner to computing means (not shown).
• the motor 7 When the motor 7 is rotated, it rotates the transmission wheel 8 (and any gear train possibly provided) which in turn rotates the input wheel 15.
• the latter also drives in rotation the bar 13 by complementary shapes (see Figure 1) while leaving free in axial translation. This causes rolling of the rollers 14 on the cam path 11 (which is fixed, the motion-transforming device 9 being fixed to the support 6) and consequently the joint translation of the bar 13 and the valve 5 in the axial direction, causing opening or closing of the valve 5.
• the motion transformation device 9 is here represented outside the valve 1.
• the input wheel 15 is in an angular position: - which corresponds to an angular position of the bar 13 ;
• the cam path 11 is configured so that the force exerted on the valve 5 when it opens is substantially linear.
• the motion transformation device 9 thus has a behavior approaching a linear system.
• a linear system is a system model that applies a linear (first degree) operator to an input signal.
• a linear system typically displays much simpler features and properties than the general nonlinear case. These linear properties improve the controllability of the system.
• the axial force applied to the valve varies linearly or quasi-linearly along the axial stroke of the valve 5.
• the curve 23 representative of the axial force applied to the valve 5 as a function of its axial stroke (valve lift) is therefore substantially a straight line.
• this curve 23 is shown in solid lines while a conventional curve 24 relating to the valves of the prior art is shown in dashed lines.
• the variation of the axial force applied to the valve 5 is not only constant but very low.
• the force at the beginning of the valve lift (point 25 of FIG. 4) can be 420 N while the force at the end of the valve lift (point 26 of FIG. 4) can be 380 N a variation of the force of about 10% over the entire stroke of the valve 5.
• the order of magnitude of the change in the force for the valves of the prior art is 1000% (see Figure 4).
• the curve 23 is here not only a straight line but is moreover quasi-horizontal.
• the cam path 11 is, in the present example, consisting of two tracks arranged face to face (diametrically opposed) on the tubular wall 12, each of these tracks being here formed of a through opening in the tubular wall 12.
• the shape of the light is a helicoid extending over the tubular wall 12. In order to obtain a constant variation valve lift axial force, this helicoid is in the present example provided with a constant helix pitch (see FIG. 3). .
• the opening behavior of the valve 1 is substantially linear in the sense that a rotation of the motor 7 at a given angle will produce substantially the same variation of force on the valve 5, regardless of the position of the valve 5.
• This variation being furthermore reduced to a minimum here, the rotation of the motor 7 by a given angle will substantially produce the application of the same force on the valve 5 regardless of the position of the valve 5.
• the substantially linear behavior of the motion-transforming device 9 may be supplemented by other elements of the kinematic chain going from the engine 7 to the valve 5 and having them also advantageously a substantially linear behavior.
• the embodiment of the present example which is particularly advantageous, groups on this kinematic chain only elements with a substantially linear behavior.
• This kinematic chain can therefore be modeled according to a linear model with satisfactory results.
• This linear model is present in the electronic device chosen to drive the valve.
• the motor 7, first of all, is here a DC motor, which gives it a substantially linear behavior.
• All gearing transmitting the rotation of the motor 7 to the input wheel 15 is also substantially linear behavior, that is to say that the teeth of the toothed wheels (here, the wheels 8 and 15) are regularly distributed on the useful circumference of said wheels. Friction is also a source of non-linearity.
• the bearing 18 here makes it possible to reduce these friction to bring the system closer to the linear behavior.
• the helical torsion spring constituting the return means 19 is also here with a substantially linear behavior, that is to say that the rotation of the input wheel 15 is directly proportional to the torque which caused this rotation (the applied torque by the transmission wheel). This behavior is obtained by choosing a substantially constant stiffness spring.
• the entire kinematic chain from the motor 7 to the valve 5 thus has a substantially linear behavior which improves its controllability.
• the task of the calculation means (not shown) for the control of the motor 7 is here reduced because, to pass from a position setpoint for the valve 5 to the corresponding command of the motor 7, the calculation means have to manipulate equations linear, requiring less computing power, better responsiveness and greater robustness.
• the command the motor 7 is here linear, that is to say made according to a linear model, the first degree.
• the gear train from the motor 7 to the input wheel 15 may comprise any number of wheels or gears.
• the valve may be any member that provides flow control (opening, closing and / or dosing) by a translational member.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Mechanically-Actuated Valves (AREA)
• Electrically Driven Valve-Operating Means (AREA)
• Valve Device For Special Equipments (AREA)
• Exhaust-Gas Circulating Devices (AREA)

Applications Claiming Priority (2)

Publications (2)

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ID=41528532

Family Applications (1)

Country Status (6)

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Family Cites Families (34)

• 2010
  • 2010-06-17 WO PCT/EP2010/058549 patent/WO2010146121A1/fr active Application Filing
  • 2010-06-17 US US13/378,372 patent/US9745901B2/en active Active
  • 2010-06-17 CN CN201080036460.XA patent/CN102482998B/zh active Active
  • 2010-06-17 KR KR1020127001239A patent/KR20120050967A/ko not_active Application Discontinuation
  • 2010-06-17 JP JP2012515496A patent/JP2012530209A/ja active Pending
  • 2010-06-17 EP EP10726947.4A patent/EP2443332B1/de active Active

Non-Patent Citations (1)

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