WO2016162623A1

WO2016162623A1 - Load emulator for electrical control of a transmission system

Info

Publication number: WO2016162623A1
Application number: PCT/FR2016/050767
Authority: WO
Inventors: Hervé MAUREL; Pascal Maurel; Carsten Lauridsen
Original assignee: Valeo Embrayages
Priority date: 2015-04-07
Filing date: 2016-04-05
Publication date: 2016-10-13
Also published as: FR3034719B1; FR3034719A1

Abstract

Load emulator (1, 200) for electrical control of a transmission system, comprising: - an input member (8, 223), distinct from a clutch pedal (2) and able to be moved if this clutch pedal (2) is actuated by a user, - an elastic return system (25) opposing this movement of the input member (8, 201), the elastic return system (25) comprising: at least one cam (26, 72, 226) collaborating with at least one follower (27, 227); of the cam (26, 72, 226) and the follower (27, 227) one moving along an axis (X) when the input member (8, 201) moves as a result of the actuation of the clutch pedal (2), and the collaboration between the cam (26, 72, 226) and the follower (27, 227) opposing this movement along the axis (X).

Description

Emulator of effort for electrical control of transmission system

The present invention relates to the electrical control of transmission system

The invention applies in particular, but not exclusively, to the control of a single or double clutch, whose idle state can be normally engaged or normally disengaged, to the control of a gearbox synchronizer for transmission. manually, with the control of a robotized gearbox, with the control of a manual gearbox with double clutch, or with the control of a coupling clutch of a heat engine with an electric machine when these two are part of a propulsion system of a hybrid vehicle.

In such a case, actuation of the clutch pedal is not intended to generate a force which acts mechanically on one or more intermediate elements in order to modify the state of the transmission system, this actuation of the pedal being against a reaction force, for example exerted by fluid present in a hydraulic control.

In the electrical control applications referred to above, no hydraulic control exerting a reaction force on the clutch pedal is used to move an element of the transmission system.

It may be desirable to create a reaction force on the pedal during actuation of the latter, that is to say when the user presses on the latter, although this actuation does not act purely mechanically on the pedal. state of the transmission system. Such a reaction effort makes it possible not to destabilize a user more accustomed to hydraulic clutch controls. This reaction effort on the pedal is then recreated by a force emulator.

Such a force emulator is for example known from DE application 2008 043 596. According to this application, the clutch pedal carries two cams and each cam interacts with a spring when the pedal is actuated. Due to this interaction, a reaction force is exerted on the pedal despite the fact that it is integrated with an electric clutch control. Such a force emulator, which has many specific components, including the clutch pedal, is thus expensive and not very interchangeable with a hydraulic control.

There is a need for a power emulator for electrical control that is inexpensive and whose implementation, when it is desired to replace a hydraulic control by an electric control, is easy.

The invention aims to meet all or part of this need and it succeeds, according to a first aspect, with a power emulator for electrical control of transmission system, comprising: - An input member, distinct from a clutch pedal and adapted to be moved in case of actuation of the clutch pedal by a user,

an elastic return system opposing this displacement of the input member, the elastic return system comprising: at least one cam cooperating with at least one roller, one of the cam and the roller moving on along an axis when the input member moves due to actuation of the clutch pedal, and the cooperation between the cam and the roller opposing this movement along the axis.

According to this first aspect, the input member of the emulator is distinct from the pedal

Clutch. The input member is for example articulated on the latter. This articulation is for example a ball joint or pivot. Alternatively, as will be seen later, the input member is not articulated on the clutch pedal, several intermediate components, such as a hydraulic control transmitter cylinder and a hydraulic pipe, then being interposed between them.

The elastic return system can only oppose the movement of the input member, the elastic return system never assists the displacement of the input member.

The cooperation between the cam and the roller can only oppose the displacement along the axis. At no time, this cooperation does not facilitate the movement of one of the cam and the roller.

With such an input member separate from the clutch pedal, it is possible to reuse a hydraulic control clutch pedal to cooperate with the emulator. The cost of the emulator and its interchangeability with a hydraulic control are thus improved.

We can reuse a standard clutch pedal.

The aforementioned displacement along an axis is assessed relative to a given reference.

When the aforementioned displacement is that of the cam, the latter undergoes a rectilinear translation along the axis. When this displacement is that of the roller, the latter rolls along this axis.

According to the examples of implementation of the invention which will be described later, this reference can be linked:

to an emulator box, or

a guide articulated on the housing of the emulator, this guide being integral with a support of the roller and guiding the translation along the axis of the cam,

- A guide articulated on the housing of the emulator, this guide being secured to a support of the cam and guiding the bearing along the axis of the roller.

The elastic return system makes it possible to generate the reaction force when the clutch pedal is actuated. The recall system can generate an effort with hysteresis, that is to say that for the same position of the clutch pedal, the reaction force is not the same depending on whether the user presses the pedal or as he releases the pedal.

The elastic return system exerts for example a reaction force similar to that exerted with a hydraulic control and a clutch in new condition. The elastic return system may be such that the curve force / stroke of the clutch pedal then, for a race from zero, first a bump and then a hollow. Alternatively, the elastic return system exerts a determined reaction effort to meet ergonomic criteria.

The emulator can be purely passive, that is to say that the elastic return system comprises only mechanical elements, such as springs or cams, being devoid of electromechanical elements such as a solenoid valve or any kind pump.

Such an emulator is then particularly cheap.

The input member may be articulated on a rod, the latter moving in translation along the axis when the input member moves. In this case, the input member can be used also in a hydraulic control, further reducing the cost of the emulator and improving its interchangeability with a hydraulic control. The joint is for example a ball joint or pivot.

Alternatively, the input member forms a rod moving in translation along the axis when the clutch pedal is actuated.

According to a first example of implementation of the first aspect of the invention, the cam is carried by the rod and the roller is pressed against the cam under the effect of an elastic restoring force.

According to this first example of implementation, the elastic return system comprises at least one spring whose axis is transverse to the axis of movement of the rod. The axis of the spring is for example an angle exactly equal to 90 ° with the axis of displacement.

According to this first example of implementation, the emulator comprises a housing and the spring extends between an end secured to the housing and an end secured to an element pressing on the roller. The spring is in particular a helical spring.

For the purposes of the present application, the housing of the emulator is not necessarily an envelope within which the latter is received wholly or partly the emulator. One or more walls assembled without defining a closed space can define a housing according to the invention and only part of the emulator is then disposed in this housing. The housing can be formed by several separate parts assembled together.

The cam then moves in translation along an axis, in a reference linked to the housing of the emulator when the input member is articulated on the rod, as already mentioned. One end of the spring is for example fixed on a spring holding piece, the holding piece being received in the housing and stationary relative thereto. The other end of the spring is for example fixed on a movable plate and pressing against the roller.

According to this first example of implementation of the invention, the cam can extend on each side of the rod, that is to say on either side of the axis of displacement, and two separate rollers may be provided, each roller being disposed on one side of the rod. Each roller can be pressed against a portion of the cam via a member pressing on the latter. In such a case, only a helical spring can be provided, this spring applying against an element pressing on one of the rollers.

Other rollers may be present, according to this first example of implementation. These rollers can cooperate with the housing of the emulator to guide the movement of the spring. These rollers can also transmit to the housing the force that the cam exerts on them.

According to this first example of implementation, the cam portion cooperating with the roller may have a profile successively comprising: a flat section, and a section forming a ramp.

As long as the roller cooperates with the flat portion, the reaction force generated by the emulator on the clutch pedal during an actuation of the latter is low. On the other hand, when a ramp cooperates with a roller, the reaction force then becomes greater.

The respective lengths of the different sections of the profile and / or the slope of the ramp may be chosen during the design of the elastic return system depending on the reaction force that is sought to be applied to the clutch pedal.

Still according to this first example of implementation of the invention, the rod may comprise several parts assembled together and moving together in translation relative to the aforementioned referential, the latter being optionally linked to the housing or to a guide articulated on this case. As already mentioned, this rod can be distinct from the input member and articulated on the latter.

The stem comprises for example:

a hollow slide articulated on the input member of the emulator,

a rod, one end of which is arranged in a housing formed in the slide and the other end of which can move beyond a ring fixed on the housing;

the cam being disposed around a portion of the rod disposed outside the slide.

A position sensor may be provided, this sensor being in particular integrated into the housing of the emulator. This position sensor measures for example the displacement of the end of the rod. The information provided by this sensor is then used to generate a set point for the electric actuator changing the state of the transmission system. According to a second example of implementation of the first aspect of the invention, the cam is still carried by the rod and the roller is always pressed against the cam under the effect of an elastic restoring force which comprises at least one spring whose axis is transverse to the axis of movement of the rod. The axis of the spring is for example with the axis of displacement an angle exactly equal to 90 °, or approximately equal to 90 °. This spring is in particular a helical spring.

According to this second example of implementation, the emulator comprises a housing and two levers, each lever being articulated on the housing and carrying a roller.

Each roller is for example rotatable about an axis fixed on one of the levers.

Each lever is for example disposed on one side of the axis of displacement, that is to say laterally with respect to the axis of displacement. The cam is then surrounded by the rollers.

Each roller can cooperate with a portion of the cam defined by a lateral face of the latter during the movement of the latter along the axis, and the spring is interposed between the levers, bearing on each of them.

According to this second example of implementation, the movement of the cam tends to exert a force to move the levers away from each other due to the cooperation of the cam with each roller. The spring, which is interposed between the two levers, exerts a force opposing this spacing of the levers, thereby providing the reaction force when actuating the clutch pedal.

The elastic return system comprises for example two separate springs, each spring bearing on each lever and being disposed only on one side of the rod.

According to this second example of implementation, the rod may be a part of the input member.

In this case, the rod moves with the aid of a guide articulated on the housing of the emulator, for example via a ball joint or pivot connection. In this case, the movement in translation of the cam is assessed in a reference linked to the guide. Alternatively, the rod is distinct from the input member, and articulated on the latter. In this case, the displacement along the axis of the cam is appreciated relative to a reference linked to the housing.

The stiffness of the springs can be chosen during the design of the elastic return system depending on the reaction force that is to be applied to the clutch pedal.

According to this second example of implementation, each lever can be formed using a folded sheet metal part with stampings or bends. These folds thus formed can maintain the axis of each roller.

The articulation of a lever on the housing is for example a pivot connection. This articulation is obtained in particular at each lever, through a cut sheet or with a folded-welded wire, to form a closed rectangle. These articulations of the levers on the housing allow the transmission to the housing of the axial forces exerted by the cam on the rollers during the actuation of the clutch pedal. Alternatively, the transmission of these forces to the housing can be effected via additional elements interposed between the housing and the levers, for example flexible blades.

According to this second example of implementation, a position sensor may be provided, this sensor being in particular integrated into the housing of the emulator. This position sensor measures for example the displacement of the rod. The information provided by this sensor is then used to generate a set point for the electric actuator changing the state of the transmission system. According to a third example of implementation of the first aspect of the invention, the cam is still carried by the rod and the roller is pressed against the cam under the effect of an elastic restoring force. The elastic return system comprises according to this third example of implementation a leaf spring (s) carrying the roller. The cam may have two lateral faces, each face extending on one side of the axis of displacement and the elastic return system may comprise two rollers, each roller cooperating with a portion of the cam defined by one of said side faces.

Each roller can be rotatable about an axis, this axis being fixed on a roller support.

The cam moves along the axis and this movement is effected against the force exerted by the rollers on the cam.

According to a first variant, the leaf spring is made in one piece using a folded sheet, and this leaf spring also forms the roller support. In a plane containing the axis of displacement, this leaf spring may have a U-shape, comprising a back and two branches. Each end of a branch can carry an axis of a roller while the rod extends through the back.

According to this first variant, the return force exerted on the cam depends on the choice of the sheet in which the leaf spring is formed. The stiffness of this sheet can be chosen during the design of the elastic return system depending on the reaction force that is to be applied to the clutch pedal.

According to a second variant, several separate blades succeeding each other around the axis of displacement form a leaf spring. In this case, a different roller support of the leaf spring can be provided. As a variant, two blades that are symmetrical with respect to the axis of displacement can act as roller supports.

Still according to this second variant, the leaf spring is then laminated. The different blades can rub on each other, generating hysteresis. According to this third example of implementation, the rod may be a part of the input member. In this case, the rod moves with the aid of a guide articulated on the housing of the emulator, for example via a ball joint or pivot connection. In this case, the displacement along the axis of the cam is appreciated relative to a reference linked to this guide. Alternatively, the rod is distinct from the input member, and articulated on the latter. In this case, the displacement along the axis of the cam is appreciated relative to a reference linked to the housing.

Still according to this third example of implementation, a position sensor may be provided, this sensor being in particular integrated into the housing of the emulator. This position sensor for example measures the displacement of the cam. The information provided by this sensor is then used to generate a set point for the electric actuator changing the state of the transmission system.

According to a fourth example of implementation of the first aspect of the invention, the roller is carried by the rod and the cam is pressed against the roller.

According to this fourth example, the rod carries the axis of the roller, the roller being rotatable about the axis. The axis of the roller then moves along the aforementioned axis of displacement, so that the roller rolls along this axis of displacement.

According to this fourth example, the elastic return system may comprise a leaf spring whose surface defines the cam cooperating with the roller. The leaf spring can be made in one piece using a folded sheet.

Two rollers can be carried by the rod, each roller being disposed on a different side of the axis of displacement. In a plane containing the axis of movement, the leaf spring may have a U-shape, comprising a back and two branches. Each branch can form a cam portion cooperating with one of the rollers while the rod extends through the back.

The return force exerted by the cams on the rollers depends on the choice of the sheet in which the leaf spring is formed. The stiffness of this sheet can be chosen during the design of the elastic return system depending on the reaction force that is to be applied to the clutch pedal.

According to this fourth example of implementation, the rod may be a part of the input member. In this case, the rod moves with the aid of a guide articulated on the housing of the emulator, for example via a ball joint or pivot connection. In this case, the rolling along the axis of the rollers is appreciated relative to a reference linked to the guide. Alternatively, the rod is distinct from the input member, and articulated on the latter. In this case, the rolling along the axis of the rollers is appreciated with respect to a reference linked to the housing.

Still according to this fourth example of implementation, a position sensor may be provided, this sensor being in particular integrated into the housing of the emulator. This position sensor measures by example the displacement of the cam. The information provided by this sensor is then used to generate a set point for the electric actuator changing the state of the transmission system.

In all the foregoing, when the input member is distinct from the rod and hinged on it, the reference relative to which the displacement of the roller or the cam is assessed can be linked to the housing, the latter supporting the stem.

Still in all the foregoing, when a portion of the input member defines the rod, the reference relative to which the displacement of the roller or cam is assessed can be linked to the aforesaid guide.

In all the above, each roller is guided in rotation on its axis by a ball bearing or needle, or by a plain bearing. The choice of this guidance in rotation of the rollers may depend on the hysteresis that it is desired to confer on the reaction force exerted on the clutch pedal by the emulator when it is actuated.

In the case where each roller is guided in rotation by a sliding bearing, when it is desired to provide such a hysteresis, it is possible for example to increase the coefficient of friction of the bearings, via the choice of the material that is used, and / or increase the ratio between diameter of a bearing and outer diameter of the roller guided in rotation by the latter.

In all the foregoing, an additional resilient return member such as a coil spring may be interposed between the input member and the emulator housing. This additional elastic return member may have an end bearing against the housing and an end bearing against the input member, and the additional resilient return member then extends between said ends. In such a case, the input member may be separate from the rod and articulated on the latter. By varying, the input member defines the rod.

Such an additional elastic return member is in particular provided in the fourth example of implementation of the first aspect of the invention.

When the additional elastic return member is integrated in the fourth embodiment of the first aspect of the invention, it can act in parallel with the leaf spring defining the cam cooperating with the roller or rollers. Such additional spring can thus generate a portion of the reaction force on the clutch pedal when the latter is actuated.

The presence of a helical spring in parallel provides in particular the following advantages: -reduction of the stresses in the leaf spring with identical dimensions,

- reduction of efforts on the pebble or rollers,

- reduction of the hysteresis of the reaction force exerted on the clutch pedal when it is actuated, in particular in the first part of the race thereof,

- Reduction of the total weight of the elastic return system, because of the higher mass / energy ratio that the coil spring has with respect to the leaf spring, - Safe operation, since the coil spring still generates at least partly the reaction force on the clutch pedal if the leaf spring is malfunctioning.

According to a second aspect of the invention, the latter also relates to a force emulator for electrical control of a transmission system, comprising:

- An input member, distinct from a clutch pedal and able to be moved in case

actuating this clutch pedal by a user,

a return system opposing this movement of the input member, the return system comprising:

- a chamber filled with a fluid,

- a piston movable in the chamber under the effect of the displacement of the input member and sealingly defining two compartments in the chamber, and

a channel of communication between the two compartments, this channel being preferably arranged outside the chamber and having a flow rate that is adjustable so as to vary the pressure opposing the displacement of the piston in the chamber when the clutch pedal is actuated .

Such an emulator makes it possible, by modifying the flow rate in the channel, to vary the pressure opposing the displacement of the piston in the chamber. It is thus possible to dynamically vary the reaction force applied to the clutch pedal when it is actuated. Such a possibility makes it possible to adapt the race-effort characteristic to the wishes of an automobile manufacturer, to the type of user, or according to the circumstances of use of the vehicle on which the transmission system is embedded.

Such an emulator may be described as an asset, comprising one or more electromechanical components, and not only mechanical components.

Such an active emulator can generate a reaction force with hysteresis, that is to say that for the same position of the clutch pedal, the reaction force is not the same depending on whether the user presses pedal or as it releases the pedal.

The emulator according to this second aspect of the invention exerts for example a reaction force similar to that exerted with a hydraulic control and a clutch in new condition.

The active emulator is for example such that the curve force / stroke of the clutch pedal then, for a race from zero, first a bump and then a hollow. Alternatively, the active emulator according to the second aspect of the invention exerts a determined reaction effort to meet ergonomic criteria.

According to this second aspect, the input member of the emulator is distinct from the clutch pedal. The input member can thus be articulated on the latter. This articulation is for example a ball joint or pivot. Alternatively, as will be seen later, the organ input is not articulated on the clutch pedal, several intermediate components, such as a hydraulic control transmitter cylinder and a hydraulic pipe being then interposed between them.

We can reuse a standard clutch pedal.

The input member may be articulated on a rod, the latter moving in translation along an axis when the clutch pedal is actuated, so as to move the piston in translation.

Alternatively, the input member forms a rod moving in translation along an axis when the clutch pedal is actuated, so as to move the piston in translation.

The fluid may be a hydraulic fluid and the return system may comprise a solenoid valve for adjusting the passage section in the channel. This changes the flow in the channel, and therefore the reaction force on the clutch pedal acting on this passage section.

Alternatively, the fluid may be a rheological fluid and the biasing system includes a variable magnetic field source for adjusting the fluid velocity in the channel. Depending on the value of the magnetic field generated, the fluid particles are thus more or less attracted into the channel, so that the flow rate in the latter varies.

The variable magnetic field source may be a coil with or without a core or, alternatively, a movable magnet.

According to this second aspect of the invention, the return system may further comprise an elastic return member opposing the displacement of the piston when the clutch pedal is actuated. This elastic return member is for example disposed in one of the compartments of the chamber and it bears against one side of a wall of this compartment, and on the other hand against the piston. This return member is then compressed when the piston moves under the effect of an actuation of the clutch pedal.

The flow in the channel is for example set by a control unit which may or may not be integrated in the engine control unit (ECU).

According to this second aspect of the invention, a position sensor may be provided. This position sensor for example measures the movement of the piston. The information provided by this sensor is then used to generate a setpoint for the electric actuator changing the state of the transmission system and / or to adjust the flow rate in the channel. According to the first or the second aspect above, when a position sensor is present, this sensor may be a non-contact linear sensor. The connector of this sensor can be placed on the engine compartment side.

The invention further provides, in a third aspect, an assembly for the electrical control of a transmission system, comprising:

a clutch pedal that can be operated by a user,

an emulator according to the first or second aspect of the invention, comprising a housing, and

- An electric actuator, adapted to control the transmission system according to the force exerted by the user on the pedal.

As already mentioned, the input member of the emulator can be articulated on the clutch pedal. In this case, the emulator is used in place of a hydraulic control transmitter cylinder.

Such an emulator is particularly interesting when the implantation of the latter near the clutch pedal is possible.

Alternatively, the assembly can comprise

a transmitter cylinder, and

a hydraulic line connected on the one hand to the emitter cylinder and on the other hand to the effort emulator,

actuating the clutch pedal by a user generating fluid displacement from the emitter cylinder to the emulator through the hydraulic line, and fluid displacement causing displacement of the input member of the emulator .

In this case, the emulator does not replace the cylinder transmitter of the hydraulic control, which remains present, as the hydraulic line, but it replaces the cylinder receiver. As before, the actuation of the clutch pedal thus does not create a force which, by purely mechanical action, makes it possible to modify the state of the transmission system.

Such an emulator is particularly interesting when the implantation of the latter near the pedal is not possible, because of a limited available space.

The above assembly may comprise a wall in which is formed an opening in which is mounted the housing of the emulator. This wall is still called "apron".

The emulator housing can be snugly mounted in the opening of the wall.

A system for fixing the housing of the emulator on the wall is for example provided, for example a bayonet mount or snap.

The aperture in the wall may be dimensioned to receive indifferently and in a controlled manner the emulator housing or a transmission system hydraulic control transmitter cylinder housing. In other words, the housing of the emulator may have dimensions for mounting interchangeably with a conventional hydraulic control transmitter cylinder in the wall, or apron.

It is thus possible to use an emulator and an electric control with a standard apron. The assembly may comprise at least one seal applying between the housing of the emulator and the wall so as to seal between this housing and this wall.

The invention further relates, in another of its aspects, to an assembly for the electrical control of a transmission system, comprising:

a clutch pedal that can be operated by a user,

a force emulator, able to generate a reaction force on the clutch pedal during an actuation thereof, and comprising a housing,

an electric actuator, able to control the transmission system according to the force exerted by the user on the pedal, and

a wall having an opening the size of which allows it to fitably and interchangeably receive the housing of the emulator and a housing of a hydraulic control transmitter cylinder.

All or some of the features mentioned above apply to this other aspect of the invention.

The invention further relates to a kit for controlling a transmission system with clutch pedal, comprising:

an emulator capable of generating a reaction force on a clutch pedal when the latter is actuated,

a transmitter cylinder capable of generating a hydraulic force when the clutch pedal is actuated,

the emulator and the emitter cylinder each comprising a housing whose dimensions allow the interchangeable mounting of these housings in an opening of a wall.

In all of the above, the emulator can be associated with a manual gearbox. The invention will be better understood on reading the following description of non-limiting examples of implementation thereof and on examining the appended drawing in which:

FIG. 1 schematically represents an emulator for electrical control of a transmission system according to a first example of implementation of a first aspect of the invention,

FIG. 2 is a sectional view along II - II of FIG. 1,

FIG. 3 is a sectional view on III-III of FIG. 2, FIG. 4 is a very schematic view of an emulator according to a second example of implementation of the first aspect of the invention,

FIG. 5 is a very schematic view of an emulator according to a third example of implementation of the first aspect of the invention,

FIGS. 6 to 11 relate to a fourth example of implementation of the first aspect of the invention, FIG. 6 being an exploded view of the emulator, FIG. 7 being a view of the emulator of FIG. 6 when assembled, FIG. 8 being a schematic sectional view of the emulator different from that of FIGS. 6 to 8 by its input member, FIG. 9 being a front view of the emulator of FIG. 6, FIG. 10 being a sectional view along XX of the emulator of FIG. 9, and FIG. 11 being a sectional view along XI-XI of the emulator according to FIG. 10,

FIG. 12 represents the reaction force applied to the clutch pedal as a function of the stroke thereof by the emulator of FIGS. 6 to 11, one of the curves showing this force when the clutch pedal is actuated while the other curve shows this effort when the clutch pedal is released.

FIGS. 13 to 15 show a variant of the fourth example of implementation of the first aspect of the invention, FIG. 13 being similar to FIG. 7 while FIGS. 14 and 15 are similar to FIGS. 10 and 11, FIG. 15 being a sectional view along XV -XV of FIG. 14,

FIG. 16 shows similarly to FIGS. 4, 5 and 8 an emulator for electrical control of a transmission system according to a second aspect of the invention,

FIG. 17 represents another example of an emulator for control of a transmission system that can belong to both the first and second aspects of the invention, and

FIG. 18 is a sectional view of the emulator of FIG. 17.

An emulator for electrical control of a vehicle transmission system will be described with reference to the figures. In the examples described below, the emulator 1 interacts with a clutch pedal 2 and with a manual gearbox not shown. The transmission system being electrically controlled, no pressure is exerted by a fluid changing the state of the transmission system when the clutch pedal 2 is actuated.

The emulator 1 thus allows the exercise of a reaction force on this pedal.

Figures 1 to 3 show a first example of implementation of an assembly comprising an emulator 1 according to a first aspect of the invention.

According to this first aspect, the emulator 1 is purely passive, that is to say that it generates the reaction force on the clutch pedal 2 by means of an elastic return system comprising only mechanical elements, such as springs or cams, being devoid of electromechanical element such as a solenoid valve or any kind of pump. The emulator 1 here comprises a housing 4 mounted in an opening 5 of an apron 6 of the vehicle. The housing 4 has dimensions allowing it to be disposed in the opening 5 interchangeably with a conventional hydraulic control transmitter cylinder housing.

In other words, the housing 4 has dimensions for using the emulator 1 with a standard apron 6. The casing 4 is then mounted fitly in the opening 5.

As can be seen in Figure 2 for example, a fastening system of the housing 4 in the opening 5 is provided, this fastening system here comprising at the housing 4 an element 9 for bayonet fixing of the housing 4 on the apron 6.

As shown in FIG. 1, a seal 7 is also provided, this seal 7 making it possible to seal the inside of the deck 6 with respect to the passenger compartment of the vehicle at the level of the opening 5.

As shown in FIG. 1, the emulator 1 comprises an input member 8, able to be articulated on the clutch pedal 2 so as to be displaced when this clutch pedal 2 is actuated by a user. of the vehicle. Here, the input member 8 is directly articulated on the clutch pedal 2. via a ball joint arranged at its end 10 coming into contact with the clutch pedal 2.

In the example shown, the input member 8 is articulated on a rod 12. This articulation is for example a ball joint arranged at the end 14 of the input member 8 opposite the end 10 allowing the connection with the clutch pedal 2.

The rod 12 is received inside the casing 4 and it moves in translation along an axis X with respect to a frame linked to the casing 4.

The rod 12 comprises in this example several pieces assembled together and moving together in translation relative to the housing. The rod 12 comprises here:

a hollow slide 15 articulated on the input member 8 and forming, with the end 14 of the latter, a ball joint, and

- A rod 17 whose one end is disposed in a housing 18 formed in the slider 15 and the other end 19 can move beyond a ring 20 fixed on the housing.

The assembly also comprises in the example shown a position sensor 22. The sensor 22 is here carried by the housing 4 of the emulator 1 and this sensor, which is in particular a non-contact and linear sensor, measures for example the displacement of the end 19 of the rod 17. The information provided by this sensor 22 can be used by a processing unit, for example integrated in the ECU, to generate a setpoint for an electric actuator changing the state of the system. transmission. It is thus possible to achieve an electric control of the "clutch by wire" type. For example, it is possible to run freewheeling, also called "coasting" in English. The emulator 1 exerts a reaction force on the clutch pedal 2 by means of an elastic return system 25 configured to oppose the movement of the input member 8 consecutive to this actuation of the pedal clutch 2.

In the example of Figure 1, this elastic return system 25 comprises a cam 26, carried by the portion of the rod 17 disposed outside the slider 15, and two rollers 27. The cam 26 moves in the example in question. translation along the axis X in the reference linked to the housing 4, and it extends on either side of this axis X, and on either side of the rod 12.

The cam 26 here has a portion 29 extending on one side of the axis X and a portion 30 extending on the other side of the axis X, and each of these portions 29 or 30 cooperates with one of the rollers 27.

Each portion 29 or 30 of the cam has an identical profile from one portion to another, this profile successively comprising: a flat section, and a section forming a ramp.

A roller 27 is, in the example of Figures 1 to 3, pressed against the portion 29 of the cam 26 via a spring 32. This spring 32 extends here along an axis Y which is orthogonal to the axis X according to which the cam 26. This plating allows the rollers 27 to oppose the displacement of the cam 26. This displacement of the cam 26 being, as already mentioned, caused by actuation of the clutch pedal 2 by a user, the cooperation between the cam 26 and the rollers 27 thus makes it possible to generate the reaction force on the clutch pedal 2 during actuation of the latter.

The spring 32 is here a helical spring which extends along the Y axis between two ends. One of these ends is integral with the housing 4, being here fixed on a holding piece 34 fixedly mounted in the housing 4 and guiding the movement of the spring 32 in the housing 4.

The other end of the spring 32 is fixed on a plate 36, this plate pressing on one of the rollers 27.

The plate 36 can also cooperate with a roller 38, also called "guide roller and reaction". This roller 38 serves to guide the movement of the spring 32 relative to the housing 4 and to transmit to the housing 4 the forces that the cam 26 exerts on it.

Two rollers 38 may be provided, each of these rollers then being arranged on one side of the rod 12. Each roller 38 may have a shape identical to that of the rollers 27.

We will now describe the operation of the emulator 1 according to the first example of implementation of the first aspect of the invention.

When the clutch pedal 2 is actuated, the input member 8 is moved via the connection formed at its end 10. This displacement is then transmitted to the rod 12 via the connection formed with the end 14 of the organ 8. The rod 12 then moves in translation along the axis X in the housing 4, and this movement tends to cooperate the ramps of the portions 29 and 30 of the cam 26 with the rollers 27. The spring 32 exerts a force on the rollers 27 opposing their displacement along the axis Y because of their cooperation with the ramps of the cam 26.

This force exerted by the spring 32 generates a reaction force on the clutch pedal 2.

The respective lengths of the different sections of the profile and / or the slope of the ramp of the portions 29 or 30 of the cam can be chosen during the design of the elastic return system 25 as a function of the reaction force that is sought. to apply on the clutch pedal.

One can for example design a return system 25 generating a force with hysteresis, that is to say that for the same position of the clutch pedal 2, the reaction force is not the same depending on whether the user presses the pedal or releases the pedal.

In an undescribed variant of this first example, the rod 12 is formed by a portion of the input member 8. In this case, the rod 12 moves inside a guide articulated on the housing of the emulator 1, and the translation of the cam 26 is appreciated relative to a reference linked to this guide.

An emulator 1 according to a second example of implementation of the first aspect of the invention will now be described with reference to FIG. This emulator 1 comprises, like that described above, an elastic return system 25 implementing a cam 26 and rollers 27.

The rod 12, shown schematically in FIG. 4, can be a part of the input member 8, in which case it moves in translation along an axis X in a reference frame linked to a guide articulated on the housing 4.

Alternatively, the rod is distinct from the input member 8 of the emulator and articulated on the latter, in which case the translational movement of the rod 12 is appreciated relative to a reference linked to the housing 4 of the emulator 1.

As can be seen in Figure 4, the cam 26 is carried by the rod 12 and two rollers 27 are provided on each side of the rod 12. Each roller 27 is pressed against a portion 29 or 30 of the cam 26 by two parallel springs 32, each of these springs 32 extending along an axis Y substantially perpendicular to the axis X of displacement of the rod 12 and the cam 26. Each spring 32 is here a helical spring. Each spring 32 is on one side of the rod 12. The emulator 2 further comprises in this example two levers 40, each lever 40 being hinged to the housing 4 via a hinge 41. Each lever 40 is disposed of a side of the X axis of displacement, that is to say in the example considered on one side of the rod 12. Each lever 40 is in the example considered formed using a sheet metal part folded with stampings. Each joint 41 can be obtained by means of a cut sheet metal or by means of a folded-welded wire, to form a closed rectangle. In an undescribed variant, additional elements are interposed between the housing 4 and the levers 40, for example flexible blades, so as to transmit to the housing 4 the forces exerted by the cam 26 on the levers 40.

At one of its ends, each lever 40 carries an axis 43 of one of the rollers 27. The folds in a lever allow the latter to maintain the axis 43 that it carries. Each roller 27 is then rotatable about a stationary axis relative to the lever 40 concerned.

Each spring 32 then extends between the two levers 40, resting at each of its ends on one of the levers 40.

According to this second example of implementation, the displacement in translation of the cam 26 tends to exert a force to move the levers 40 away from each other. Each spring 32 exerts a force opposing this spacing of the levers 40, thereby providing the reaction force on the clutch pedal 2, upon actuation thereof. As described in connection with the first example of implementation of the invention, the assembly comprising an emulator according to the second exemplary implementation of the invention may comprise a position sensor of the displacement of the rod 12.

An emulator according to a third embodiment of the first aspect of the invention will now be described with reference to FIG.

According to this third example, the cam 26 is still carried by the rod 12. The rod 26 is here formed by a portion of the input member 8. The latter can move in translation along an axis X inside the a guide 50 hinged, for example via a ball joint 51, on the housing 4. The translation movement is then assessed with respect to a reference linked to the guide 50.

According to this third example of implementation, the elastic return system further comprises two rollers 27 which each interact with a portion 29 or 30 of the cam 26, each of these portions 29 and 30 extending only on one side of the rod 12 and being formed by a lateral face of the cam 26.

The return system here is devoid of coil spring. A leaf spring 55 is provided here, this leaf spring exerting on the rollers 27 a force pressing them against a portion 29 or 30 of the cam 26.

Each roller 27 is rotatable about an axis 43, the latter being fixed on the leaf spring 55 which acts as a roller support. The leaf spring is here fixed on the guide 50, so that the translation of the rod 12 is appreciated with respect to a reference linked to the support of the rollers 27.

In the example shown, the leaf spring 55 is made in one piece using a folded sheet. In a plane containing the axis of displacement X, this leaf spring here has a U-shape, comprising a back 57 and two branches 56. Each end of a branch 56 here carries an axis 43 of a roller 27 while the rod 12 extends through the back 57. The choice of the sheet to make the leaf spring 55 can allow to choose the elastic restoring force exerted on the rollers 27 to press against the cam 26. Thus, the choice of the sheet can adjust the reaction force exerted on the clutch pedal 2 when it is pressed.

In a variant not shown, the leaf spring is other, in particular being laminated.

Several blades spaced around the X axis can then be provided.

In another variant not described, the rod 12 is distinct from the input member 8, and articulated on the latter. The translational movement of the rod 12 is then assessed with respect to a reference linked to the housing 4.

Still according to this third example of implementation, a position sensor may be provided.

A set with an emulator according to a fourth embodiment of the invention will now be described with reference to FIGS. 6 to 11.

As can be seen in Figure 6, the housing 4 is for example in two parts, screws 60 then allowing the assembly of these two parts of the housing 4.

According to this fourth example of implementation, the cam is not displaced in translation by the rod 12. The cam 26 is formed by a leaf spring 70. The leaf spring 70 is made in one piece to the using a folded sheet. In a plane containing the axis of displacement X, this leaf spring here has a U-shape, comprising a back 71 and two branches 72. Each branch 72 defines a running surface which, other than at its free end , extends parallel to the axis X. The leaf spring 70 is in the example considered secured to the housing 4 by means of the screws 60 used to assemble the two parts of the housing 4.

Still according to this fourth example of implementation, the rod 12 carries the axes 43 of the rollers 27. Each roller 27 is disposed on one side of the X axis of displacement. The rollers 27 can roll along the X axis, via their cooperation with the branches 72 of the leaf spring 70.

The leaf spring thus makes it possible to press the branches 72, which correspond to the cam portions 28 and 29 described above, against the rollers 27.

As can be seen in FIGS. 6 and 7, the rod 12 can be articulated on the input member 8, in which case the rolling along the axis X of the rollers 27 can be evaluated with respect to a linked reference frame to the case 4.

In the variant illustrated in Figure 8, the rod 12 is formed by a portion of the input member 8. In this case, the rod 12 moves in translation within a guide 50, similarly to this which has been described with reference to the second and third examples of implementation of the invention. In this variant, the leaf spring 70 which defines the cam is fixed on the guide 50, so that the rolling of the rollers 27 along the axis X is assessed in a reference frame linked to the leaf spring 70. Still according to this fourth example of implementation, a position sensor can be provided

In all the examples which have just been described, each roller 27 can be guided in rotation on its axis 43 by a ball or needle bearing, or by a plain bearing.

Each of the elastic return systems described with reference to Figures 1 to 11 can be used to generate a reaction force on the clutch pedal when actuating the latter which has a hysteresis.

As represented in fact in FIG. 12, which is a graph obtained with the emulator according to the fourth implementation example, but which can be transposed to the other examples of implementation previously described, the reaction force exerted on the Clutch pedal 2 depending on its actuating stroke may be different depending on whether the user presses the clutch pedal or releases it.

We can indeed see by comparing the curve 80, which corresponds to a support on the pedal 2, and the curve 81, which corresponds to a release of the pedal, that different values of reaction force exist for the same race of the pedal.

As can be seen in Figure 12, the elastic return system 25 exerts for example on the clutch pedal 2 a reaction force similar to that which would be exerted on the latter with a hydraulic control and a clutch in the state new. Each curve 80 and 81 then presents, for a race increasing from zero, first a hump and then a hollow.

A variant of the fourth embodiment of the invention will now be described with reference to FIGS. 13 to 15. The emulator 1 according to this variant differs essentially from that described with reference to FIGS. 6 to 11 in that an additional helical spring 90 is provided. This helical spring 90 is here interposed between the housing 4 and a support formed in the input member 8. The spring 90 is here connected to both the housing 4 and the input member 8. This spring 90 acts and in parallel with the leaf spring 70 to press the rollers 27 against the cam portions 72 formed by the branches of the leaf spring 70.

The spring 90 acts in this variant in parallel with the leaf spring 70 and provides a portion of the reaction force exerted on the clutch pedal 2 when the latter is actuated.

An assembly comprising an emulator 100 according to a second exemplary implementation of the invention will now be described with reference to FIG.

This emulator 100 is integrated with an electrical control system of vehicle transmission system, as is the emulator described with reference to Figures 1 to 12. This emulator 100 thus interacts with a clutch pedal not shown in Figure 13 and with a manual gearbox also not shown. Since the transmission system is electrically controlled, no pressure is exerted by a fluid that changes the state of the transmission system. transmission when the clutch pedal is operated. The emulator 100 thus allows the exercise of a reaction force on this pedal.

According to this second aspect, the emulator 100 is active, that is to say that it generates the reaction force on the clutch pedal using a return system comprising one or more electromechanical elements as will be seen later.

This emulator 100 comprises, similarly to the emulator 1 described above, an input member 101, distinct from the clutch pedal and adapted to be articulated on the latter so as to be moved when this pedal is actuated. clutch by a user. An end 102 of this input member 101 forms for example a ball joint with the clutch pedal.

The emulator 100 further comprises a chamber 103 filled with a liquid and a piston 104 movable in the chamber 103 under the effect of the displacement of the input member 101. The piston 104 defines in a sealed manner two compartments 105 and 106 in room 103.

As can be seen, a channel 107, which is in the example described, arranged outside the chamber 103, allows communication between the compartments 105 and 106. As will be seen later, this channel 107 has an adjustable flow rate , which makes it possible to vary in a controlled manner the pressure difference between the compartments 105 and 106.

Similarly to the emulator 1 previously described, the emulator 100 comprises a housing 110 mounted in an opening 111 of the deck 112 of the vehicle. The housing 110 has dimensions allowing it to be disposed in the opening 111 interchangeably with a conventional hydraulic control transmitter cylinder housing.

Still in a manner similar to the emulator 1 of FIGS. 1 to 12, a system for fastening the housing 110 in the opening 111 is provided, this fastening system comprising here at the housing 110 an element 113 for fixing the housing to a bayonet 110 on the apron 111. A seal 115 is also provided, this seal 115 for sealing the interior of the deck relative to the passenger compartment of the vehicle at the opening 111.

In the example of Figure 13, the input member 101 forms a rod and the rod moves in translation in a guide 120 articulated on the housing 110, for example via a ball joint.

In the example shown in FIG. 13, the liquid present in the chamber 103 is a hydraulic liquid and a solenoid valve 122 is disposed in the channel 107. This solenoid valve 122 is controlled by a control unit 124 which communicates with the ECU of the vehicle, being for example integrated into the vehicle ECU.

The solenoid valve 122 makes it possible to regulate the flow rate in the channel 107 by varying the passage section in the channel 107. In a variant, the liquid present in the chamber 103 is a rheological liquid and the flow rate in the channel 107 is regulated by a variable magnetic field source such as a coil, with or without a core, or a movable magnet. The magnetic field can thus, depending on its value, circulate more or less liquid particles in the channel 107.

The chamber 103, the piston 104 and the adjustable flow rate channel 107 constitute, according to this second aspect of the invention, a return system for generating a reaction force on the clutch pedal when it is actuated.

In the example described, this return system further comprises a helical spring 125 disposed in the compartment 105 and opposing the decrease in the volume of the latter when the piston 104 moves due to the actuation of the pedal. clutch.

As can be seen in FIG. 13, a position sensor 127 is also present, this sensor measuring in the example described the displacement of the rod 101. The information provided by this sensor 127 can be used to generate a setpoint for the electric actuator modifying the state of the transmission system and / or regulating the flow rate in the channel 107.

The operation of the emulator 100 shown in FIG. 16 will now be described.

When the clutch pedal is actuated by a user, the input member 101, and therefore the rod, moves in translation in the guide 120 and in the chamber 103. This displacement of the rod 101 moves the piston 104. This displacement is done against the force exerted by the spring 125 and against the force exerted by the pressure in the compartment 105 and resulting from the flow of liquid in the channel 107.

Thus, the emulator 100 is controlled by the control unit 124 so that the pressure difference in the chamber 103 on either side of the piston 104 leads to a predefined reaction force being applied to the clutch pedal.

With the emulator 100, it is possible to dynamically vary the reaction force applied to the clutch pedal when it is actuated. Such a possibility makes it possible to adapt the race-effort characteristic to the wishes of an automobile manufacturer, to the type of user or according to the circumstances of use of the vehicle on which the transmission system is embedded.

The emulator 100 exerts for example on the clutch pedal a reaction force similar to that which would be exerted on the latter by a hydraulic control and a clutch in new condition.

In a not shown variant of the emulator 100, the input member 101 is articulated on a rod, and this rod moves in translation in the chamber 103, thus displacing the piston 104 in translation. In all the examples just described, the input member 8 or 101 of the emulator 1 or 100 is articulated on the clutch pedal of the vehicle and the conventional hydraulic control is completely removed. The invention is however not limited to such a configuration, as will now be seen with reference to Figures 14 and 15.

In the example of Figures 14 and 15, described in connection with the first aspect of the invention but which also applies to the second aspect of the invention, the assembly comprises

an emitter cylinder 210, and

a hydraulic pipe 211.

In a known manner, the emitter cylinder 210 is connected to a low pressure reservoir 212 and to the hydraulic pipe 211. The actuation of the clutch pedal 2 displaces a piston in the emitter cylinder 210, which causes a sending of liquid under pressure in the hydraulic line 211.

The hydraulic pipe 211 is connected to an inlet 213 formed in the housing 220 of the emulator 200. This inlet 213 thus allows the fluid displaced by the actuation of the clutch pedal 2 to come into contact with the body input 223 of the emulator 200 and move it. In the example shown, the input member 223 of the emulator 200 forms a rod moving in the housing 220 of the emulator 200.

This rod carries a cam 226 and the displacement of this cam 226 is effected against an elastic force exerted on this cam 226 by rollers 227 on which a helical spring 232 presses, similarly to what has been described with reference to FIGS. 3.

This force exerted by the rollers 227 on the cam 226 is propagated through the hydraulic pipe 211 to the emitter cylinder 210, so that a reaction force is generated on the clutch pedal 2 by the emulator 200.

According to variants that are not described, the emulator 200 reminder system is different, for example that according to the second example of implementation, or the third example of implementation or the fourth example of implementation of the first aspect of FIG. the invention which have been described previously. According to another variant not described, the reminder system of the emulator 200 is that according to the second aspect of the invention, shown in FIG. 13.

Claims

claims

A force emulator (1, 200) for electrical control of transmission system, comprising:

- an input member (8, 223), distinct from a clutch pedal (2) and able to be moved when this clutch pedal (2) is actuated by a user,

an elastic return system (25) opposing this displacement of the input member (8, 201), the elastic return system (25) comprising: at least one cooperating cam (26, 72, 226) with at least one roller (27, 227), one of the cam (26, 72, 226) and the roller (27, 227) moving along an axis (X) when the input member (8, 201) moves due to the actuation of the clutch pedal (2), and the cooperation between the cam (26, 72, 226) and the roller (27, 227) opposing this displacement along the axis (X).

2. Emulator according to claim 1, the input member (8) being articulated on a rod (12) moving in translation along the axis (X) when the input member (8) moves. .

3. Emulator according to claim 1, the input member (8) forming a rod (12) moving in translation along the axis (X) when the clutch pedal is actuated (2).

4. Emulator according to claim 2 or 3, the cam (26, 226) being carried by the rod (12) and the roller (27, 227) being pressed against the cam (26) under the effect of a force of elastic return.

5. Emulator according to claim 4, the elastic return system (25) comprising at least one spring (32) whose axis (Y) is transverse to the axis of displacement (X) of the rod (12) .

6. Emulator according to claim 5, comprising a housing (4, 220) and the spring (32, 232) extending between an end secured to the housing (4, 220) and an end secured to a member (36) supporting on the roller (27, 227).

7. Emulator according to claim 5, comprising a housing (4) and two levers (40), each lever (40) being articulated on the housing (4) and carrying a roller (27), each roller (27) cooperating with a portion (29, 30) of the cam during movement along the axis (X) thereof, and the spring (32) being interposed between the two levers (40), and supported on each lever (40) .

8. Emulator according to claim 7, the elastic return system (25) comprising two springs (32), the rod (12) being disposed between these two springs (32).

9. Emulator according to claim 4, the elastic return system (25) comprising a leaf spring (s) (55) carrying the roller (27).

10. Emulator according to claim 9, the leaf spring (s) (55) being made in one piece using a crushed sheet or being formed by the meeting of blades arranged around the rod (12). .

11. Emulator according to claim 2 or 3, the roller (27) being carried by the rod (12) and the cam (72) being pressed against the roller (27).

12. Emulator according to claim 11, the elastic return system (25) comprising a leaf spring (70) whose surface (72) defines the cam.

13. Emulator according to claim 12, the elastic return system (25) comprising an additional elastic return member (90), in particular a helical spring, acting in parallel with the leaf spring (70).

14. An assembly for the electrical control of a transmission system, comprising:

a clutch pedal (2) actuable by a user,

an emulator (1, 200) according to any one of the preceding claims, comprising a housing (4, 220), and

- An electric actuator, adapted to control the transmission system according to the force exerted by the user on the clutch pedal (2).

15. The assembly of claim 14, the input member (8) of the emulator (1) being articulated on the clutch pedal (2).

16. The assembly of claim 14 comprising:

an emitter cylinder (210), and

a hydraulic pipe (211) connected on the one hand to the emitter cylinder (210) and on the other hand to the force emulator (200),

actuating the clutch pedal (2) by a user generating a displacement of fluid from the emitter cylinder (210) to the emulator (200) through the hydraulic line (211), and this fluid displacement causing the moving the input member (223) of the emulator (200).

17. An assembly according to any one of claims 14 to 16, comprising a wall (6) in which is formed an opening (5) in which is mounted the housing (4) of the emulator (1).

18. The assembly of claim 17, the aperture (5) having dimensions allowing it to indifferently receive indifferently the housing (4) of the emulator (1) or a casing cylinder transmission transmitter hydraulic control system .

19. The assembly of claim 17 or 18, comprising at least one seal (7) applied between the housing (4) of the emulator (1) and the wall (6) so as to seal between this housing (4) and this wall (6).