FR3079980A1 - ELECTRIC ACTUATOR FOR A HEATING, VENTILATION AND / OR AIR CONDITIONING SYSTEM FOR A MOTOR VEHICLE - Google Patents

Abstract

The present invention relates to an electric actuator (1) adapted to drive a mobile element (20) for a heating, ventilation and / or air conditioning system for a motor vehicle, comprising: - an electric motor (10); - a satellite ring (12) comprising at least one satellite (120); - a driving wheel (11) adapted to be rotated by said electric motor (10) and adapted to rotate said satellite gear (12); - an output wheel (13) comprising an output star (130) adapted to drive said movable element (20) of said ventilation, heating and / or air conditioning system; according to which said electric actuator (1) further comprises: - A worm (14) adapted to be rotated by said satellite gear (12), in direct connection with said output wheel (13) and adapted to rotate said output wheel (13).   

Description

TECHNICAL FIELD OF THE INVENTION

The present invention relates to an electric actuator adapted to drive a movable element for a heating, ventilation and / or air conditioning system for a motor vehicle.

It finds a particular, but not limiting, application in heating, ventilation and / or air conditioning systems for motor vehicles.

TECHNOLOGICAL BACKGROUND OF THE INVENTION

An electric actuator adapted to drive a mobile element for a heating, ventilation and / or air conditioning system for a motor vehicle, known to a person skilled in the art, comprises:

- an electric motor comprising a stator and a rotor;

- a satellite crown;

- An output wheel adapted to be rotated by said satellite gear.

These three elements are arranged along the motor axis of said electric motor. The electric actuator is either too large or does not have enough torque to be integrated close to the mobile element. Therefore, an additional kinematic part is used. Said kinematic part is adapted to be rotated by said output wheel and is adapted to rotate said movable member of said heating, ventilation and / or air conditioning system.

A disadvantage of this state of the art is that the kinematic part creates noise and it weakens the electric actuator mechanically.

In this context, the present invention aims to solve the aforementioned drawback.

GENERAL DESCRIPTION OF THE INVENTION

To this end, the invention provides an electric actuator adapted to drive a mobile element for a heating, ventilation and / or air conditioning system for a motor vehicle, comprising:

- an electric motor;

- a satellite ring comprising at least one satellite;

- a driving wheel adapted to be rotated by said electric motor and adapted to rotate said satellite gear;

- an output wheel comprising an output star adapted to drive said mobile element of said ventilation, heating and / or air conditioning system;

according to which said electric actuator further comprises:

- A worm screw adapted to be rotated by said satellite gear, in direct connection with said output wheel and adapted to rotate said output wheel.

Thus, as will be seen in detail below, by removing the kinematic part between the output wheel and the movable element, the volume of the electric actuator is reduced, the noise problems are eliminated and the problems are eliminated. mechanical that could occur on said kinematic part. Furthermore, the use of an endless screw makes it possible to have sufficient torque to drive the movable element so that the electric actuator can be placed close to said movable element.

According to nonlimiting embodiments, the electric actuator may also include one or more additional characteristics among the following:

According to a nonlimiting embodiment, said drive wheel is overmolded with the drive shaft of said electric motor. This reduces the number of parts of the electric actuator to be assembled.

According to a nonlimiting embodiment, said electric motor, said driving wheel, said crown gear and said worm screw extend along the same motor axis of said electric motor. This reduces the size of said electric actuator. Said drive wheel, said sun gear, and said worm screw thus rotate around the motor axis of said electric motor.

According to a nonlimiting embodiment, said electric actuator further comprises a housing, and said electric motor, said driving wheel, said planet gear, said worm and said output wheel are housed in said housing. This eliminates an electric motor housing usually used to house only the electric motor.

According to a nonlimiting embodiment, said satellite ring comprises a plurality of satellites. This improves the efficiency of the electric actuator.

According to a nonlimiting embodiment, said drive wheel, said satellite gear and said worm screw form a planetary gear train. This provides sufficient torque for the electric actuator in a very small space.

According to a nonlimiting embodiment, said output wheel is toothed on its periphery. It can thus be driven by the worm.

According to a nonlimiting embodiment, said output wheel extends along a plane perpendicular to the motor axis of said electric actuator. This makes it possible to have an output wheel which is not located in the motor axis of the electric motor and thus to increase the axial compactness of said electric actuator.

According to a nonlimiting embodiment, said electric actuator further comprises an electronic card further comprises an electronic card which extends along a plane parallel to the motor axis of said electric motor. This allows to have an electrical connector directly in front of said electronic card.

According to a nonlimiting embodiment, the drive wheel is in direct connection with at least one satellite of said satellite ring.

The drive wheel comprises teeth which cooperate with teeth of said at least satellite of said satellite ring. This allows direct drive of said satellite ring gear by said drive wheel.

According to a nonlimiting embodiment, the output star is in direct connection with the movable element of said heating, ventilation and / or air conditioning system. In particular, it comprises teeth which cooperate with teeth of the movable element of said heating, ventilation and / or air conditioning system. This allows a direct drive of said movable element by said output wheel, without additional kinematic part.

According to a nonlimiting embodiment, the output star has a complementary shape with part of the movable element. This provides a direct link between the output star and the moving element.

According to a nonlimiting embodiment, said at least one satellite comprises two stages of gears with different diameters and a different number of teeth. This increases the torque and reduces the speed of rotation.

According to a nonlimiting embodiment, the satellite ring comprises an odd number of satellites. This helps to balance the satellite crown.

A heating, ventilation and / or air conditioning system for a motor vehicle is also proposed, said heating, ventilation and / or air conditioning system comprising a mobile element and an electric actuator adapted to drive said mobile element, according to which said electric actuator is characterized. according to any of the preceding characteristics.

BRIEF DESCRIPTION OF THE FIGURES

The invention and its various applications will be better understood on reading the description which follows and on examining the figures which accompany it:

- Figure 1 shows a kinematic diagram of an electric actuator for heating, ventilation and / or air conditioning for motor vehicles, said electric actuator comprising a housing, an electric motor, a drive wheel, an electronic card, a crown satellite, a worm and an output wheel, according to a nonlimiting embodiment;

- Figure 2 shows an exploded view of the electric actuator of Figure 1, without the housing, according to a non-limiting embodiment;

- Figure 3a shows an assembled profile view of the electric actuator of Figures 1 and 2 without the housing, according to a non-limiting embodiment;

- Figure 3b is a sectional view of a portion of the electric actuator of Figure 3a, according to a non-limiting embodiment;

- Figure 4 shows a perspective view of the electric motor with a motor shaft on which is positioned the drive wheel of the electric actuator of Figures 1 and 2, according to a non-limiting embodiment;

- Figure 5 shows a perspective view of the electric motor of Figure 4 with a fixed sun gear of the satellite gear of the electric actuator of Figures 1 and 2, according to a non-limiting embodiment;

- Figure 6 shows a perspective view of the electric motor of Figure 5 on which is positioned a support of the satellite gear of the electric actuator of Figures 1 and 2, according to a non-limiting embodiment;

- Figure 7 shows a perspective view of the electric motor of Figure 6 with satellites of the satellite ring of the electric actuator of Figures 1 and 2, according to a non-limiting embodiment;

- Figure 8 shows a bottom view of a portion of the satellite gear of the electric actuator of Figures 1 and 2, according to a non-limiting embodiment;

- Figure 9 shows a perspective view of the part of the satellite ring of Figure 8 with the worm of the electric actuator of Figures 1 and 2, according to a non-limiting embodiment;

- Figure 10 shows a sectional view of the electric motor, the drive wheel, the assembled satellite gear of the electric actuator of Figures 1 and 2, according to a non-limiting embodiment;

- Figure 11a shows a perspective view of the housing of the electric actuator of Figures 1 and 2, according to a non-limiting embodiment;

- Figure 11b shows a sectional view of Figure 11a;

- Figure 11c shows the sectional view of Figure 11b in which the electric motor, the drive wheel, the satellite gear, the worm and the output wheel of the electric actuator of Figures 1 and 2 are positioned; and

- Figure 11d shows a perspective view of the housing of Figure 11a in which the electric motor, the drive wheel, the satellite gear, the worm and the output wheel of the electric actuator of Figures 1 and 2 are positioned .

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Identical elements, by structure or by function, appearing in different figures keep, unless otherwise specified, the same references.

The electric actuator 1 is described with reference to Figures 1 to 11d according to non-limiting embodiments.

The electric actuator 1 is adapted to drive a mobile element 20 (illustrated diagrammatically in FIG. 1) of a heating, ventilation and / or air conditioning system (not illustrated), commonly called HVAC system "Heating Ventilation and Air Conditioning >> in English, for motor vehicle.

In the following description, the heating, ventilation and / or air conditioning system is also called an HVAC system.

By motor vehicle is meant any type of motor vehicle. The electric actuator 1 is suitable for mounting in the HVAC system. In a nonlimiting embodiment, the electric actuator 1 is adapted to be mounted on one side of a wall of the HVAC system while the mobile element 20 is mounted on the other side.

In a nonlimiting embodiment, the HVAC system is positioned under the dashboard of the motor vehicle.

An HVAC system provides thermal management of a passenger compartment of the motor vehicle. It allows the movement of a flow of air sent into the passenger compartment, as well as its thermal conditioning, in particular with a view to heating and / or cooling said passenger compartment.

To this end, the HVAC system comprises a heat exchanger for performing a heating function, in particular a radiator, and a heat exchanger for ensuring a cooling function, in particular an evaporator. The air flow circulating in the HVAC system is channeled to one and / or the other of the heat exchangers to achieve the desired thermal conditioning. The HVAC system delivers the heat treated air flow in particular areas of the passenger compartment, such as a lower area of the passenger compartment, called the foot, a windshield area and / or an upper area of the passenger compartment, called ventilation, especially located near the passenger face of the vehicle.

The circulation of the air flow through the heat exchangers and the selective distribution of the treated air flow to the various areas of the passenger compartment mentioned above is effected by the actuation of mobile elements 20, arranged at the through distribution ducts arranged in the HVAC system. A mobile element 20 is electrically controlled each by an electric actuator 1 or more mobile elements 20 are electrically controlled by an electric actuator 1. The electrical instruction which they receive from the electric actuator 1 is transformed into a movement of the mobile elements 20 for bring them to a certain position. The electric actuator 1 thus makes it possible to automatically control one or more mobile elements 20.

In a nonlimiting embodiment, these mobile elements 20 are air flaps. This nonlimiting embodiment is taken in the following description.

As illustrated in FIGS. 1 and 2, the electric actuator 1 comprises:

- an electric motor 10 comprising a stator and a rotor (not shown);

- a driving wheel 11;

a satellite ring 12 comprising at least one satellite 120;

- an output wheel 13;

- a worm screw 14.

The drive wheel 11, the satellite gear 12 and the worm 14 form a gear train which is a speed reducer.

In a nonlimiting embodiment, the electric actuator 1 also comprises a housing 15.

In a nonlimiting embodiment, the electric actuator 1 also comprises an electronic card 16.

As illustrated in Figures 1 and 2, the electric motor 10, the drive wheel 11, the satellite gear 12, and the worm 14 are coaxial. Thus, they extend along the same axis which is the motor axis 102 of said electric motor 10.

As illustrated in FIG. 1, it will be noted that the axis 202 of the mobile element 20 extends along a plane perpendicular to the motor axis 102. The axis 202 of the mobile element 20 merges with the axis 132 of the output wheel 13.

Thus, the mobile element 20 and the output wheel 13 extend along a plane perpendicular to the motor axis 102.

In a nonlimiting embodiment, the electric actuator 1 is adapted to detect that the mobile element 20, such as the air flap, reaches the end of its travel. At the end of the race, there is a physical stop. The electric actuator 1 is capable of detecting the limit switch. It thus includes a stop detection function. This makes it possible to cut the control of the electric motor 10 so that there is no noise due to the movable element which comes into abutment and so that there is no wear of the teeth of the different wheels 11, 12, 13 of the electric actuator 1. The electric actuator 1 is at this time called intelligent electric actuator. The stop detection function and its realization being known to the skilled person, it is not described in more detail here.

The different elements of the electric actuator 1 are described in detail below.

• B.P.Îtier.15

The housing 15 is illustrated in FIGS. 1, 11 a to 11 d.

It allows the electric actuator 1 to be mounted in the HVAC system.

In a nonlimiting embodiment, the housing 15 is made of a plastic material. This makes it possible to have a housing 15 that is lighter, less expensive and less noisy than if it is made of a metallic material.

The housing 15 is adapted to receive the electric motor 10, the drive wheel 11, the satellite gear 12, the output wheel 13 and the worm 14. Thus, the electric motor 10, the drive wheel 11, the satellite gear 12 , the worm 14 and the output wheel 13 are housed in a single housing 15.

As illustrated in FIG. 11a, the housing 15 comprises a receptacle 15b and a cover 15a adapted to cover and protect the other elements 10, 11, 12, 13, 14 of the electric actuator 1.

In nonlimiting examples, the receptacle 15b and the cover 15a are assembled together by clips or by gluing.

The cover 15a makes it possible to close the housing 15 after the electric motor 10, the drive wheel 11, the satellite gear 12, the worm 14 and the output wheel 13 have been inserted into the receptacle 15b.

As illustrated in FIGS. 11b and 11c, in a nonlimiting embodiment, the housing 15 comprises:

- A housing 150 in which the electric motor 10 and the satellite gear 12 can be housed;

a housing 153 in which the output wheel 13 can be housed. The housing 153 comprises an enclave 1531 in which the worm 14 can be housed.

In a nonlimiting embodiment illustrated in FIG. 11b, the housing 15 further comprises a shoulder 152 at the level of said enclave 1531, shoulder 152 on which the teeth 141 of the worm 14 can rest as illustrated on the figure 11 c.

It will be noted that the mobile sun gear 122 of the satellite gear 12 being secured to the worm 14, it is held in position by said shoulder 152 when it is encapsulated in the housing 150 of the housing

15. Namely, it is held in position so as not to be in contact with the support 121 nor with the fixed sun gear 123.

The housings 150, 153 and shoulder 152 are partly shaped in the receptacle 15b and partly in the cover 15a.

In a nonlimiting embodiment, the box 15 further comprises:

- An opening 155 illustrated in FIGS. 11a and 11b into which an output star 130 of the output wheel 13 described below can be inserted. This opening 155 passes through the receptacle 15b and the cover 15a;

- a mounting device 151 on the HVAC system. The mounting device 151 makes it possible to mount the box 15 on the HVAC system but also to keep the receptacle 15b and the cover 15a assembled.

In the nonlimiting example illustrated, the mounting device 151 is composed of two ears 151 crossed by one or more orifices adapted to each receive a screw, the orifices thus forming attachment points. Two fixing points are distributed diametrically opposite from each other which allows the screws which cooperate with the mounting device 151 to hold the cover 15a and the receptacle 15b so as to prevent them from coming apart when a pressure force is applied to the cover 15a. Such a pressure force is applied when the movable element 20 is mounted on the output wheel 13.

In a nonlimiting embodiment, the housing 15 further comprises an electrical plug 156. The electrical plug 156 opens out from the housing 15 and extends perpendicular to the motor axis 102. It forms an electrical interface between the electronic card 16 described below and an electrical connector (not illustrated) which transmits control signals and power signals to respectively control and supply said electronic card 16. These control signals and power signals are generated by an electronic control unit (not illustrated ) of the motor vehicle.

In a nonlimiting embodiment illustrated in FIG. 11b, the housing 15 further comprises an axial compensation device 154 for the axis 140 of the worm 14.

The axial compensation device 154 makes it possible to avoid a respective offset of the worm 14 which could cause premature wear of the various gears used.

In a nonlimiting embodiment, the axial compensation device 154 is a stop in the housing 15 in which the axis 140 of the worm 14 is wedged.

The worm 14 and thus guided axially by the axial compensation device 154 up to the shoulder 152.

• Electric motor. 10

The electric motor 10 is illustrated in whole or in part in FIGS. 1 to 7, 10 and 11c.

In nonlimiting embodiments, the electric motor 10 is a bipolar stepping motor or a three-phase motor, or a direct current motor with or without brushes.

It is housed in the housing 15.

The electric motor 10 includes:

- a motor shaft 100 which defines the motor axis 102 illustrated in Figures 1 and 3b;

- a rotor and a stator with coils (not shown).

The electric motor 10 is adapted to drive the driving wheel 11 in rotation, thus ensuring the rotation of the satellite gear 12, the worm 14 and the output wheel 13, and consequently the setting in motion of the mobile element 20.

In particular, in a nonlimiting embodiment, the rotor of the electric motor 10 drives the drive wheel 11 in rotation.

The motor shaft 100 is connected to the rotor of the electric motor 10.

In a nonlimiting embodiment illustrated in FIGS. 1 and 3b for example, the drive wheel 11 is rotated by the electric motor 10 via the drive shaft 100 which transmits the rotational movement of the rotor to said drive wheel 11.

In a nonlimiting embodiment illustrated, the electric motor 10 also comprises at least one positioning device 101 for the fixed sun gear 123 of the satellite ring gear 12 described below.

In a nonlimiting embodiment illustrated in FIG. 4, the positioning device 101 is a positioning pin. In a nonlimiting example, the electric motor 10 comprises four positioning pins.

• RQue.motrice.l.l,

The drive wheel 11 is illustrated in Figures 1,2, 3b to 10 and 11c.

The driving wheel 11 is also called the internal planetary.

As described above, in a nonlimiting embodiment, the drive wheel 11 is in connection with the motor shaft 100 of the electric motor

10.

The drive wheel 11 is suitable for:

- be driven in rotation by the electric motor 10; and

- rotating the satellite crown 12.

The drive wheel 11 rotates around the motor axis 102.

In a nonlimiting embodiment illustrated in FIG. 4, for example, the motor shaft 100 and the drive wheel 11 are integral with one another. The electric motor 10 is thus in direct connection with the drive wheel 11.

In a nonlimiting variant, the motor shaft 100 and the drive wheel 11 are fitted. The drive wheel 11 is tightly mounted on the motor shaft 100.

In another nonlimiting variant, the drive wheel 11 is overmolded with the motor shaft 100. This allows a simpler and faster assembly of the electric actuator 1 because there are fewer parts to assemble. As illustrated in FIG. 6, the drive wheel 11 is positioned between two plates 121a and 121b of a support 121 of the satellite gear 12 described below. This allows it to cooperate with at least one satellite 120 of the satellite ring gear 12. In the example illustrated in the figures, it cooperates with two satellites 120.

The drive wheel 11 is in direct connection with a satellite 120.

In a nonlimiting embodiment, the drive wheel 11 comprises an external toothed surface whose teeth cooperate with teeth of each satellite 120 so as to set it in rotation. It is thus toothed on its periphery.

To play on the value of the output torque and the speed, we play on the number of teeth of the drive wheel 11 and on the set of gears.

Thanks to the planetary gear train (described below), the output torque is increased to move the movable element 20. It is therefore not necessary to have a very powerful electric motor 10. This saves energy to run it. In a nonlimiting example, the electric motor 10 has a power of at least 0.2 N / cm. Thus, the more the electric motor 10 has a low power, the more the output torque must be high, this by playing on the gear ratio, for example the planetary gear train.

• CQurQnne.satellite.12

The satellite crown 12 is illustrated in whole or in part in FIGS. 1 to 3b, 5 to 10 and 11c.

As illustrated in FIG. 2, the satellite crown 12 includes:

- at least one satellite 120, otherwise called planetary;

- a support 121, otherwise called satellite carrier;

- a mobile sun gear 122, otherwise called a mobile crown 122;

- a fixed sun gear 123, otherwise known as a fixed crown 123.

The satellite crown 12 is suitable for:

- be driven in rotation by the drive wheel 11;

- rotate the worm 14.

o Satellite._1.20

A satellite 120 is adapted to rotate on itself. It rotates around its axis, which is a mechanical axis 121c described below. Furthermore, it is suitable for turning around the motor axis 102.

As illustrated in the bottom view of FIG. 8, in a nonlimiting embodiment, a satellite 120 is formed by at least one toothed wheel, also called a gear, the teeth of which cooperate with:

- The teeth formed on the drive wheel 11, so as to effect a rotational movement; and

- The teeth formed on the movable sun gear 122 so as to set it in rotation.

As illustrated in FIG. 7, in a nonlimiting embodiment, the teeth of the satellite 120 also cooperate with the teeth formed on the fixed sun gear 123.

In a nonlimiting embodiment, the teeth of a satellite 120 are located on its outer periphery. This makes it possible to make the satellite 120 cooperate with the driving wheel 11 and at the same time the mobile planetary 123 and the mobile planetary 122.

In a nonlimiting embodiment, the satellite gear 12 comprises a plurality of satellites 120. This makes it possible to improve the efficiency of the gear train formed by the drive wheel 11, the satellite gear 12 and the worm 14, because there is less slippage between the teeth which cooperate with each other; in other words, there are fewer tooth jumps. In the nonlimiting example illustrated, it comprises two satellites 120.

In another nonlimiting example not illustrated, the satellite crown 12 comprises an odd number of satellites 120. This makes it possible to balance the satellite crown 12. The number of three satellites 120 is a good compromise between efficiency and size.

In a nonlimiting embodiment illustrated in FIGS. 7 to 10, the satellite ring gear 12 is double-stage. Thus, a satellite 120 comprises two stages of gears 120a, 120b.

In this case, the driving road 11 cooperates with a single gear stage of a satellite 120. Said gear stage 120a is the one closest to the electric motor 10. And the mobile sun gear 122 cooperates with the other stage d gears, the one furthest from the electric motor 10.

It will be noted that the more the number of stages is increased, the more the gear ratio of the gear train increases, and the more the torque at the output increases.

In a nonlimiting embodiment, a satellite 120 comprises two stages of gears 120a, 120b with different diameters and a different number of teeth. In a nonlimiting embodiment, a satellite 120 is a single piece.

The gear stage 120b, otherwise known as the upper gear stage 120b, has a diameter greater than the gear stage 120a, otherwise known as the lower gear stage 120a. This increases the torque and reduces the speed.

As illustrated in FIG. 10, the lower gear stage 120a is suitable for:

- cooperate with the drive wheel 11 as described above. It is in direct connection with said drive wheel 11;

- cooperate with the fixed sun gear 123. It is in direct contact with the fixed sun gear 123. It thus rolls on the fixed sun gear 123 when it rotates around a mechanical axis 121c.

As illustrated in FIG. 10, the upper gear stage 120b is adapted to cooperate with the movable sun gear 122 so as to drive it in rotation. It is in direct connection with said movable sun gear 122.

It will be noted that when a satellite 120 of the satellite ring 12 comprises two stages of gears, this is called a double-stage planetary gear train.

o Support. 121

As illustrated in FIG. 6, the support 121 is made up of two plates 121a, 121b arranged opposite one another and substantially parallel to one another.

The plate 121a, known as the lower plate, is located opposite the bottom 123a of the fixed sun gear 123. The plate 121b, said upper plate, is located opposite the bottom 122a of the movable sun gear 122.

The two plates 121a, 121b are adapted to maintain the mechanical axes 121c on which the satellites 120 rotate. The satellites 120 are thus arranged between the two plates 121a and 121b. The support 121 also comprises an orifice 1210 through which the motor shaft 100 can be inserted.

The satellite crown 12 rotates around the motor axis 102. In particular, it is its support 121 which rotates around said motor axis 102 so as to rotate the satellites 120 around said motor axis 102.

The support 121 is encapsulated between the fixed planetary 123 and the mobile planetary 122 of the satellite ring gear 12 as illustrated in FIG. 10.

The support 121 is adapted to rest on the fixed sun gear 123. In particular, its plate 121a rests on the bottom 123a of the fixed sun gear 123 as illustrated in FIG. 6.

o. Planetary mobi.le.122

As illustrated in FIGS. 8 to 10, in a nonlimiting embodiment, the mobile sun gear 122 cooperates with:

- Each satellite 120 so as to perform a rotational movement;

- An axis 140 of the worm 14 so as to rotate it.

The mobile sun gear 122 rotates around the motor axis 102.

The movable sun gear 122 is formed by a toothed wheel, also called a gear, the teeth of which cooperate with the teeth formed on each satellite 120 so as to effect a rotational movement.

It has a bottom 122a adapted to position itself opposite the plate 121b of the support 121.

The movable sun gear 122 is thus in direct connection with the satellites 120 and the worm 14. In a nonlimiting embodiment, its teeth are located inside the wheel which forms it so as to allow cooperation with the teeth of each satellite 120.

In particular, the mobile sun gear 122 is in direct connection with the upper gear stage 120a. The mobile sun gear 122 is thus driven in rotation by the upper gear stage 120b of each satellite 120.

It is not in contact with the mobile sun gear 123 to avoid friction or with the support 121 of the satellite crown 12.

The upper gear stage 120b of the satellites 120 and the movable planetary gear 122 form a second stage of reduction of the gear ratio of the planetary gear train.

o Planetary.fixed. 123

As illustrated in FIGS. 3b, 5 to 7, 10, in a nonlimiting embodiment, the fixed sun gear 123 is adapted to cooperate with each satellite 120. It thus allows the satellites 120 to rotate on themselves around 'a mechanical axis 121c.

The fixed sun gear 123 is formed by a toothed wheel, also called a gear, the teeth of which cooperate with the teeth formed on each satellite 120. It is in direct connection with the satellites 120. In particular, it cooperates with the stage of gears lower 120a of each satellite 120. In a nonlimiting embodiment, its teeth are located inside the wheel which forms it so as to allow cooperation with the teeth of each satellite 120.

The fixed sun gear 123 rests on the electric motor 10. It is positioned on the electric motor 10 by means of the four positioning pins 101 seen previously. To this end, in a nonlimiting embodiment, the fixed sun gear 123 comprises positioning orifices 1231 (illustrated in FIG. 2) adapted to cooperate with the positioning pins 101. The fixed sun gear 123 further comprises an orifice 1230 illustrated in Figure 5 by which the drive shaft 100 of the electric motor 10 can be inserted.

The lower gear stage 120a of the satellites 120, the movable sun gear 123 and the drive wheel 11 form a first stage of reduction of the gear ratio of the epicyclic gear train.

• Worm screw.14

The worm is illustrated in Figures 1 to 3b, 9, 10 and 11c.

The worm 14 extends along the motor axis 102 and rotates around said motor axis 102.

The worm 14 is suitable for:

- be driven in rotation by said satellite ring gear 12;

- rotating said output wheel 13.

The worm 14 includes:

- an axis 140;

- teeth 141.

In a nonlimiting embodiment, the axis 140 is metallic and the toothing is plastic.

In a nonlimiting embodiment, the worm 14 is in direct connection with the crown gear 12 via its axis 140.

In a nonlimiting embodiment, the worm 14 is integral with the satellite gear 12. This makes it possible to reduce the steps of assembling the electric actuator 1. In particular, as illustrated in FIGS. 3a and 3b , the axis 140 of the worm 14 is integral with the mobile sun gear 122 of the satellite ring gear 12. They rotate at the same speed. The axis 140 is rotated by the movable sun gear 122.

The worm 14 is adapted to drive the output wheel 13 in rotation. The toothing 141 cooperates with the teeth of the output wheel 13 which allows said output wheel 13 to rotate in rotation along an axis 132 illustrated in the Figure 3a which extends along a plane perpendicular to the motor axis 102. The output wheel 13 and the planetary gear train (composed of the drive wheel 11, the satellite gear 12 and the worm 14) thus have different axes. Note that the two axes 132 and 102 do not intersect.

The drive wheel 11, the satellite gear 12 and the worm 14 which have been described extend along the motor axis 102. They thus form an epicyclic gear train, otherwise called epicyclic speed reducer.

An epicyclic gear train provides sufficient torque in a very small space. This also makes it possible to have a holding torque (called "holding torque") sufficient to have a non-reversibility of the electric actuator 1 when it is not supplied. Thus, in a nonlimiting example, the holding torque is less than 100N / cm (Newton per centimeter). In other words, the torque to be applied to rotate the electric actuator 1 when it is not supplied is greater than or equal to 100N / cm. The electric actuator 1 is thus non-reversible (it cannot rotate) when there are forces less than 100N / cm.

An epicyclic gear train thus makes it possible to have a sufficient holding torque to prevent the movable element 20 from moving during vibrations which can occur when the motor vehicle is in motion, for example when it passes over a donkey . Thus, any noise from the movable element 20 is eliminated.

Furthermore, the fact of having a sufficient holding torque to prevent the movable element 20 from moving makes it possible to cut off the power supply to the electric actuator 1 after a thermal adjustment (adjustment of the heating, the air conditioning and / or ventilation) was made to put the movable member 20 in a determined position. It is not necessary to operate said electric actuator 1 so that the mobile element 20 remains in the determined position. This saves less energy.

It is necessary to choose the value of the degree of inclination of the teeth 141 of the worm 14 so as to have a good compromise between the friction of the teeth 141 with the teeth 1310 of the output wheel 13, and the torque transmission. . The more straight the teeth 141, the more friction there will be. The more the teeth 141 are inclined, the less torque is transmitted.

Thanks to the use of the worm 14 in the planetary gear train, it is possible to reduce the diameter of the electric motor 10 and thus save in terms of material cost, magnetic material (for the stator coils) and in terms of energy used to run the electric motor 10.

• Exit wheel.13

The output wheel 13 is illustrated in FIGS. 1 to 3b, 11 c and 11 d.

The output wheel 13 is suitable for:

- be driven in rotation by the worm 14;

- drive the movable element 20 of the HVAC system.

In particular, as illustrated in FIG. 3a, the output wheel 13 comprises:

- an external sun gear 131; and

- an output star 130.

The outer sun gear 131 is adapted to be driven in rotation by the worm 14. In particular, the outer sun gear 131 is adapted to cooperate with the teeth 141 of the worm as described above. The external sun gear 131 comprises an external toothed surface 1310 (illustrated in FIGS. 3a and 3b), the teeth of which cooperate with the teeth 141 of the worm 14.

The output wheel 13 rotates around an axis 132.

The axis of rotation 132 of the output wheel 13 extends along a plane perpendicular to the axis of rotation (which is the motor axis 102) of the worm

14.

The output star 130 is adapted to drive the mobile element 20 so that the latter starts to move. The mobile element 20 thus has the same rotational speed as the output star 130.

In particular, the output star 130 is adapted to cooperate with a projecting part 200 (shown diagrammatically in FIG. 1) of the mobile element 20.

The output star 130 thus has a complementary shape with the projecting part 200 of the movable element 20.

In a nonlimiting embodiment, the output star 130 is hollow and has grooves on its internal surface as illustrated in FIG. 2 for example. The output wheel 13 is thus in this non-limiting embodiment a so-called female output wheel. In this case, the movable element 20 comprises a complementary male projecting part which cooperates with the so-called female output wheel.

In another nonlimiting embodiment, the output wheel 13 is a so-called male output wheel. In this case, the mobile element comprises a complementary female projecting part which cooperates with the so-called male output wheel.

The exit star 130 has a sufficient height to push in the projecting part 200 of the movable element 20.

As illustrated in FIGS. 11a, 11c and 11d, when all the elements 10, 11, 12, 13, 14, and 16 are enclosed in the housing 15, only the output star 130 of the output wheel 13 is accessible from outside the housing 15 in order to insert the projecting part 200 of the movable element 20 therein.

It will be noted that the output star 130 is traversing on either side of the housing 15. This makes it possible to be able to insert the projecting part 200 of the movable element 20 on one side or the other of the actuator electric 1. This allows greater flexibility in installing the electric actuator 1 in the HVAC system.

• Carte.éjectrpnigue.16

The electronic card 16 is illustrated in FIGS. 1 to 3b and 11 c.

In a nonlimiting embodiment, the electronic card 16 is flat and extends along a plane parallel to the motor axis 102.

As illustrated in FIGS. 1 and 3a, in a nonlimiting embodiment, the electronic card 16 is positioned adjacent to said electric motor 10. In a nonlimiting embodiment, it is fixed to said electric motor 10 by means of mounting clips (not shown).

The electronic card 16 comprises an electrically insulating substrate carrying a plurality of conductive tracks and a plurality of electronic components (not shown). In a nonlimiting embodiment, it also includes a device for controlling the electric motor 10, called “driver” in English, adapted to receive the control signals and the power signals for the electric motor 10 coming from the electric plug. 156. It thus comprises a plurality of pins 160 (illustrated in FIG. 1) adapted to be connected to an electrical connector.

Furthermore, the electronic card 16 is connected to the stator coils (not shown) and thus allows their electrical supply.

The electronic card 16 is in a nonlimiting example a printed circuit card called PCBA in English (“Printed Circuit Board Assembly”).

The elements of the electric actuator 1 are assembled as follows, in a nonlimiting embodiment. In this nonlimiting embodiment, the drive wheel 11 is molded with the motor shaft 100.

The steps are as follows:

- Attachment of the electronic card 16 to the electric motor 10. This step can be carried out before or after any step preceding the positioning of the assembly of the electric actuator 1 in the housing 15;

- positioning of the fixed sun gear 123 on the electric motor 10 thanks to the positioning pins 101 and fitting onto the motor shaft 100 of the electric motor 10 which supports the drive wheel 11 as illustrated in FIG. 5;

positioning of the satellites 120 in their support 121 around the mechanical axes 121c. This step can be performed before or after positioning the fixed sun gear 123;

- mounting of the support plate 121b on the mechanical axes 121c. This step can be performed before or after positioning the fixed sun gear 123;

- Positioning of the 121-satellite 120 support assembly on the fixed planet 123 and fitting of the 121-satellite 120 support assembly on the motor shaft 100 as illustrated in FIG. 7;

- fitting of the mobile planetary assembly 122 - worm 14 on the satellites 120 as illustrated in FIG. 10;

- positioning of the electronic card assembly 16 - electric motor 10 - driving wheel 11-fixed planetary 123-satellites 120 - mobile planetary 122 - worm 14 in the housings 150-153-1531 -154 of the housing 15 of the actuator electric 1 provided for this purpose as illustrated in Figure 11c;

- positioning of the output wheel 13 in the housing 153 provided for this purpose as illustrated in Figure 11c. The worm 14 rests on the shoulder 152;

- placement of the cover 15a on the receptacle 15b so as to close the housing 15 as illustrated in FIG. 11 d.

The electrical connector can then be plugged into the electrical plug 156 to allow transmission of control and power signals.

The housings 150-153-1531-154 and the shoulder 152 of the housing 15 thus maintain in position the various elements 10, 11, 12, 13, 14, 16 of the electric actuator 1.

It will be noted that if the drive wheel 11 is not overmolded with the motor shaft 100, it is mounted tight on said motor shaft 100 before the positioning of the fixed sun gear 123.

Of course, the description of the invention is not limited to the application and to the embodiments described above.

Thus, in addition to use in an HVAC system, the electric actuator 1 can also be used to drive a mobile element 20, such as a flap located on the front face of the motor vehicle to regulate the intake air at the level of the engine compartment and improve the aerodynamic penetration of the motor vehicle;

Thus, the electric actuator 1 can be used in any system which requires driving a mobile element in rotation;

Thus, in another nonlimiting embodiment, the housing 15 is made of a metallic material.

Thus, in another nonlimiting embodiment, the electronic card 16 is further adapted to send diagnostic signals from the electrical actuator 1 to a CAN or LIN type multiplexed network via the cooperating electrical connector (not illustrated). with electrical plug 156.

Thus, in another nonlimiting embodiment, the mobile element 20 is a kinematic part in connection with several air flaps. The output star 130 of the output wheel 13 is thus adapted to cooperate with said kinematic part. The electric actuator 1 is thus suitable for electrically controlling several air flaps.

Thus, in another nonlimiting embodiment, the satellite crown 12 comprises a single stage or more than two stages of satellites 120.

Thus, in another nonlimiting embodiment, the satellite ring gear 12 comprises an odd number of satellites. This allows the satellite crown 12 to be balanced.

Thus, the invention described has the following advantages in particular:

- It makes it possible to have an electric actuator 1 which is axially more compact due to the positioning of the output wheel 13 next to the planetary gear train and not above it. The height is thus reduced;

- It gives the possibility of avoiding having an intermediate kinematic part between the movable element 20 and the electric actuator 1. Thus, there is no noise created by an intermediate part in motion. By eliminating the intermediate part, the weight of the HVAC system as a whole is reduced and the number of parts for moving the movable element 20 is reduced. Thus, this advantage is particularly advantageous because of the trend that manufacturers have of increasing the number of mobile elements 20 in motor vehicles to increase the thermal comfort zones for users of motor vehicles. In addition, there is less wear on the HVAC moving element chain which allows better reliability and better robustness of the HVAC system;

- It allows a gain in efficiency and a suppression of noise coming from the mobile element 20 thanks to the planetary gear train;

- Thanks to the single housing 15 of the electric actuator 1, it avoids having two separate housings including a housing for the electric motor 10 and including another housing for the gear train formed by the driving wheel 11, the satellite crown 12, the worm 14 and the output wheel 13;

- It allows through the use of the worm 14 in the planetary gear train to have enough torque to drive the output wheel 13;

- it allows thanks to the worm 14 to easily drive the output wheel 13 without the need for a high degree of precision on the teeth 141 and the teeth of the output wheel 13, unlike a solution which would use an intermediate wheel with a bevel gear for driving said output wheel 13.

Claims (10)

1. Electric actuator (1) adapted to drive a mobile element (20) for a heating, ventilation and / or air conditioning system for a motor vehicle, comprising: - an electric motor (10); - a satellite ring (12) comprising at least one satellite (120); - a driving wheel (11) adapted to be rotated by said electric motor (10) and adapted to rotate said satellite gear (12); - an output wheel (13) comprising an output star (130) adapted to drive said movable element (20) of said ventilation, heating and / or air conditioning system; according to which said electric actuator (1) further comprises: - A worm (14) adapted to be rotated by said satellite gear (12), in direct connection with said output wheel (13) and adapted to rotate said output wheel (13). 2. Electric actuator (1) according to claim 1, according to which said drive wheel (11) is overmolded with the motor shaft (100) of said electric motor (10). 3. Electric actuator (1) according to claim 1 or claim 2, wherein said electric motor (10), said driving wheel (11), said satellite gear (12) and said worm (14) extend according to the same axis which is the motor axis (102) of said electric motor (10). 4. Electric actuator (1) according to any one of the preceding claims 1 to 3, according to which said electric actuator (1) further comprises a housing (15), and according to which said electric motor (10), said driving wheel ( 11), said satellite gear (12), said worm (14) and said output wheel (13) are housed in said housing (15). 5. Electric actuator (1) according to any one of the preceding claims 1 to 4, according to which said satellite ring (12) comprises a plurality of satellites (120). 6. An electric actuator (1) according to any one of the preceding claims 1 to 5, according to which said drive wheel (11), said planet gear (12) and said worm (14) form a planetary gear train. 7. Electric actuator (1) according to any one of the preceding claims 1 to 6, according to which said output wheel (13) is toothed on its periphery. 8. Electric actuator (1) according to any one of the preceding claims 1 to 7, according to which said output wheel (13) extends along a plane perpendicular to the motor axis (102) of said electric actuator (1). 9. Electric actuator (1) according to claim 8, wherein said electric actuator (1) further comprises an electronic card (16) which extends along a plane parallel to the motor axis (102) of said electric motor (10 ). 10. A heating, ventilation and / or air conditioning system for a motor vehicle, said heating, ventilation and / or air conditioning system comprising a mobile element (20) and an electric actuator (1) adapted to drive said mobile element (20), according to which said electric actuator (1) is characterized according to any one of the preceding claims 1 to 9.