Actuator, in particular of electromechanical actuator

Abstract

The invention relates to an actuator (1) comprising a housing (8) and a rotary output member (5) which is arranged to supply an actuation torque, this rotary member being rotatable relative to the housing (8) about an axis of rotation (XR) and comprising a first portion (14) and a second portion (15) which are assembled together, the housing (8) being provided with two opposing axial stops (17, 18), on each of which each portion of the rotary output member bears respectively so that, once assembled and bearing on the axial stops (17, 18) of the housing, the rotary output member is kept axially stationary in the direction of the axis of rotation (XR).

Description

Description Title of the invention: Actuator, in particular of the electromechanical type [1] [The present invention relates to an actuator, in particular of the electromechanical type, in particular for application on a vehicle, for example a motor vehicle. [2] The vehicle can be land, sea or air. [3] Patent application DE102020120241 A1 discloses an electromechanical actuator with an electric motor of the brushless direct current motor type. This type of motor is referred to in English as a "brushless direct current motor" or "BLDC motor". This actuator serves as a flap actuator in a valve. For control and monitoring, the electric motor of the actuators can be equipped with sensors to determine motor parameters such as the rotor position, the rotor speed or the rotation angle of an actuator element coupled to the rotor. [4] The actuator described in this patent application DE102020120241 A1, comprises, in a housing closed by a cover, a BLDC type electric motor with a stator and a rotor. Also provided is a reduction gear train for transmitting a torque produced by the motor to an output pinion. This output pinion is formed in one piece with a hollow shaft passing through an opening in the housing to be connected to a valve element. A three-branch support member holds the upper end of the output pinion. [5] Fig. 1 shows an actuator 100 of a type substantially similar to that described in patent application DE102020120241 A1. This actuator comprises an electric motor 101 which drives, via a set of gears (not shown), an output pinion 102. This pinion 102 comprises a toothed wheel 103 and a hollow shaft 104 made in a single piece. The upper part of the pinion 102 is held by a support member 106 forming a first smooth pivoting bearing 107. A second bearing pivoting 108 is present at the lower end of the hollow shaft 104. These bearings 107 and 108 are radial type supports. An axial stop is provided between the output pinion 102 and an annular wall 110 of the housing. The alignment of the single-piece part (output pinion / hollow shaft) in the two bearings 107 and 108 requires precision in the dimensions and positioning of these bearings. This imposes strict manufacturing tolerances. In addition, the single-piece part pivots in two bearings 107 and 108, therefore in two locations, which generates more wear. In addition, the presence of a Hall effect sensor above a magnet carried by the single-piece part (output pinion / hollow shaft) requires the use of the support member 106. [6] The invention aims in particular to improve an actuator of the type described with reference to figure 1. [7] The invention thus relates to an actuator comprising a housing, a rotary output member arranged to provide an actuating torque, this rotary member being rotatable relative to the housing along an axis of rotation and comprising a first part and a second part assembled together, the housing being provided with two opposing axial stops on each of which each part of the rotary output member bears respectively so that once assembled and bearing on the axial stops of the housing, the rotary output member is kept fixed axially in the direction of the axis of rotation. [8] An axial stop is understood to mean a stop capable of blocking translation in one of the directions along the axis of rotation of the rotating member. [9] Thus, according to the invention, one of the axial stops ensures translational locking in one of the two directions of the axis of rotation, and the other of the axial stops ensures translational locking in the opposite direction of the axis of rotation. These opposing axial locks thus axially immobilize the rotary output member on its axis of rotation, a member which cannot translate in either direction along the axis of rotation.

[0010] Thus the rotating output member can rotate around its axis of rotation, without the possibility of translation along this axis.

[0011] Thanks to the invention, the translational locking in the axis of rotation of the rotary member can be achieved simply by assembling the first and second parts on the axial stops. For example, it is not necessary to use an additional part such as the support part 104 in the actuator of FIG. 1.

[0012] According to one aspect of the invention, the first and second parts of the rotary member sandwich the axial stops of the housing.

[0013] According to one aspect of the invention, the first part of the rotary output member comprises a toothed sector, in particular in the form of a toothed wheel, configured to cooperate with a complementary gear element. This complementary gear element is in particular part of a gear train between an electric motor and the rotary output member.

[0014] According to one aspect of the invention, the diameter of this toothed sector, in particular of this toothed wheel, corresponding to the maximum diameter of the rotary output member, this diameter being measured perpendicular to the axis of rotation.

[0015] According to one aspect of the invention, the second part of the rotary output member comprises a male or female socket, arranged to cooperate with an actuating member, in particular of the type arranged to perform a valve function.

[0016] According to one aspect of the invention, the actuating member is associated with a flap to selectively take an open or closed position for the circulation of a fluid in a valve.

[0017] According to one aspect of the invention, the second part of the rotary output member comprises a female socket formed by a cavity configured to cooperate with an actuating member so as to transmit the actuating torque to it.

[0018] According to one aspect of the invention, this cavity has a substantially polygonal cross-section, for example hexagonal or octagonal, or a petal-shaped cross-section, arranged to receive a rod of complementary shape to the actuating member.

[0019] According to one aspect of the invention, the second part is arranged to rotate in an outlet opening, in particular circular, of the housing, thus forming a pivot connection between this second part and the housing.

[0020] According to one aspect of the invention, the second part of the rotary output member extends through this output opening.

[0021] According to one aspect of the invention, the second part is arranged to rotate in contact with an internal wall of this outlet opening of the housing.

[0022] According to one aspect of the invention, the housing, with its outlet opening, thus forms a plain bearing for the second part of the rotating member.

[0023] Thanks to the invention, only one plain bearing is needed to perform the pivot function, which reduces frictional wear.

[0024] Furthermore, the invention allows, due to this single bearing, a greater sizing tolerance in the manufacture of parts.

[0025] According to one aspect of the invention, the second part of the rotary output member comprises a cylindrical barrel engaged in the output opening of the housing.

[0026] According to one aspect of the invention, the housing comprises an internal annular wall provided with a free end, which free end forms one of the axial stops. This annular wall is said to be internal because it is inside the housing. This housing is in particular closed by a cover, for example a substantially flat cover.

[0027] According to one aspect of the invention, this free end is a flat. This flat forms one of the axial stops.

[0028] According to one aspect of the invention, this internal annular wall comprises, over a portion of the height, a radially internal chamfer adjacent to the free end.

[0029] According to one aspect of the invention, the toothed sector, in particular the toothed wheel, of the rotary output member is in axial abutment on this free end.

[0030] According to one aspect of the invention, one of the axial stops is thus present inside the housing.

[0031] According to one aspect of the invention, this internal annular wall forming an axial stop surrounds the outlet opening of the housing.

[0032] According to one aspect of the invention, this internal annular wall forming an axial stop has a cylindrical shape with a circular section.

[0033] According to one aspect of the invention, this internal annular wall forming an axial stop is concentric with the barrel of the second part of the rotary output member.

[0034] According to one aspect of the invention, this internal annular wall forming an axial stop is made in one piece with the rest of the housing.

[0035] According to one aspect of the invention, the housing comprises an external annular wall provided with a free end or a shoulder, this free end or this shoulder forming the other of the axial stops. This annular wall is said to be external because it is outside the housing.

[0036] So one of the axial stops is inside the housing and the other of the axial stops is outside the housing.

[0037] According to one aspect of the invention, this free end of the external annular wall is a plate.

[0038] According to one aspect of the invention, the second part of the rotary output member, in particular a cylindrical barrel of this second part, comprises a collar, in particular annular, in axial abutment on this free end or this annular shoulder of the external annular wall of the housing.

[0039] According to one aspect of the invention, this external annular wall forming an axial stop surrounds the outlet opening of the housing.

[0040] According to one aspect of the invention, this external annular wall forming an axial stop has a cylindrical shape with a circular section.

[0041] According to one aspect of the invention, this external annular wall forming an axial stop is concentric with the barrel of the second part of the rotary output member.

[0042] According to one aspect of the invention, this external annular wall forming an axial stop is made in one piece with the rest of the housing.

[0043] According to one aspect of the invention, the internal diameter of the external annular wall is smaller than the internal diameter of the internal annular wall forming an axial stop.

[0044] According to one aspect of the invention, the actuator comprises a seal, in particular an annular seal, bearing on a periphery of the second part of the rotary member, to provide a seal opposite the outlet opening.

[0045] According to one aspect of the invention, this seal comprises an annular lip bearing in a sealed manner on the cylindrical barrel of the second part of the rotary output member.

[0046] According to one aspect of the invention, this seal further comprises a rim bearing tightly on an internal face of the housing.

[0047] According to one aspect of the invention, this seal has a U-shaped cross-section bearing on the internal annular wall forming an axial stop.

[0048] According to one aspect of the invention, the seal is inserted into an annular housing defined between the inner annular wall of the housing and the toothed wheel of the rotary output member.

[0049] According to one aspect of the invention, the seal, which is an added part, is made in particular of silicone or rubber.

[0050] According to one aspect of the invention, the rotary output member carries a magnet participating in the operation of an angular position sensor.

[0051] According to one aspect of the invention, the first and second parts of the rotary output member are at least one of them, preferably both of them, made in a single piece.

[0052] According to one aspect of the invention, the first and second parts of the rotary output member are welded together, in particular by laser welding or by ultrasonic welding or by friction welding.

[0053] According to one aspect of the invention, the first and second parts of the rotary output member comprise respective male and female shapes that fit together, and these shapes are welded together.

[0054] According to one aspect of the invention, the first part of the rotary output member comprises a female shape defined by an annular groove and the second part of the rotary member comprises a male shape defined by an axial crown, fitting into the annular groove of the first part.

[0055] According to one aspect of the invention, the second part of the rotating member comprises a cylindrical barrel closed by a transverse wall and the crown is connected to this transverse wall.

[0056] According to one aspect of the invention, the free end of the crown is chamfered.

[0057] According to one aspect of the invention, the second part of the rotating member comprises a shoulder, in particular annular, on which the toothed wheel of the first part rests.

[0058] According to one aspect of the invention, the first part of the rotating member comprises a hollow column connecting to the toothed wheel, and this hollow column comprises a housing for housing a magnet of a position sensor, in particular of the Hall effect type.

[0059] According to another aspect of the invention, the first and second parts of the rotary output member are assembled together by snap-fastening.

[0060] According to one aspect of the invention, at least one of the first and second parts of the rotary output member comprises snap-fastening shapes, in particular in the form of snap-fastening tabs, cooperating with the other of the first and second parts.

[0061] According to one aspect of the invention, the second part of the rotary member comprises snap-fastening tabs arranged to retain the first part of the rotary member on a shoulder of this second part.

[0062] After snapping in, the rotating member rests on the two opposing axial stops.

[0063] According to one aspect of the invention, these snap-on tabs rest on the toothed wheel of this first part of the rotating member.

[0064] According to one aspect of the invention, these snap-on tabs are arranged along a circular circumference.

[0065] According to one aspect of the invention, these legs are symmetrical to each other by rotation. Alternatively, the legs may have different shapes from each other.

[0066] According to one aspect of the invention, there are four of these snap-on tabs.

[0067] According to one aspect of the invention, the second part of the rotary member comprises a retaining groove into which the toothed wheel of the first part of the rotary member is inserted, after passing through the snap-in tabs.

[0068] According to one aspect of the invention, the first part of the rotating member comprises a toothed wheel and a hollow column connecting to the toothed wheel, this hollow column comprising windows in each of which a snap-on tab head engages.

[0069] According to one aspect of the invention, the windows are arranged adjacent to the gear wheel.

[0070] According to one aspect of the invention, the windows are arranged on a circular perimeter.

[0071] According to one aspect of the invention, the actuator is of the electromechanical type.

[0072] According to one aspect of the invention, the actuator comprises an electric motor and a gear train actuable by the electric motor to transmit torque to the rotary output member.

[0073] According to one aspect of the invention, the actuator comprises an electronic card which carries an angular position sensor for detecting the angular position of the rotary output member.

[0074] According to one aspect of the invention, the actuator is associated with a valve for directing a heat transfer fluid in a cooling circuit, or a non-return valve for a heat transfer fluid in a cooling circuit, or a throttle valve for a heat transfer fluid in a cooling circuit.

[0075] The invention also relates to a method for manufacturing an actuator, the method comprising the following steps: i) providing a housing, ii) providing a rotary output member arranged to generate an actuating torque, this rotary member being rotatable relative to the housing along an axis of rotation and comprising a first and a second part assembled together, the housing being provided with two opposing axial stops on each of which each part of the member bears respectively, iii) assembling the first and second parts of the rotary output member so that once assembled and bearing on the axial stops of the housing, the rotary output member is kept axially fixed in the direction of the axis of rotation.

[0076] According to one aspect of the invention, the assembly is carried out by welding the first and second parts of the rotary output member.

[0077] According to one aspect of the invention, the assembly is carried out by snap-fastening the first and second parts of the rotating output member.

[0078] Other characteristics and advantages of the invention will appear more clearly on reading the following description, given by way of illustrative and non-limiting example, and the appended drawings among which:

[0079] - [Figure 1] illustrates, schematically and partially, in section, an actuator which does not relate to the invention;

[0080] - [Figure 2] illustrates, schematically and partially, in perspective, an actuator according to an exemplary implementation of the invention;

[0081] - [Figure 3] illustrates, schematically and partially, in perspective, the actuator of [Figure 2], without the cover;

[0082] - [Figure 4] illustrates, schematically and partially, one face of the actuator of [Figure 2];

[0083] - [Figure 5] illustrates, schematically and partially, in section along V-V, the actuator of [Figure 2];

[0084] - [Figure 6] illustrates, schematically and partially, in perspective, the first part of the rotary member of the actuator of [Figure 2];

[0085] - [Figure 7] illustrates, schematically and partially, in perspective, the second part of the rotary member of the actuator of [Figure 2];

[0086] - [Figure 8] illustrates, schematically and partially, in section, an actuator according to an exemplary implementation of the invention;

[0087] - [Figure 9] illustrates, schematically and partially, in perspective, the first part of the rotary member of the actuator of [Figure 8].

[0088] [Figure 2] to [Figure 7] show an actuator 1 of the electromechanical type, which comprises an electric motor 2, for example of the BLDC type, and a gear train 3, of the reduction type, actuable by an output pinion 4 of the electric motor 2 to transmit a torque to a rotary output member 5.

[0089] The gear train 3 comprises, in a known manner, several toothed wheels 6 of different diameters.

[0090] The actuator 1 comprises a housing 8 closed by a substantially flat cover 9, both of which are here made of plastic. The housing 8 comprises, in a manner known per se, an electrical connection base 7 arranged to cooperate with an electrical connector not shown.

[0091] The actuator 1 further comprises an electronic card 10 which carries an angular position sensor 11, of the Hall effect type, for detecting the angular position of the rotary output member 5, as can be clearly seen in Figure 5.

[0092] The actuator 1 can be associated with a valve for directing a heat transfer fluid in a cooling circuit, or a non-return valve for a heat transfer fluid in a cooling circuit, or a throttle valve for a heat transfer fluid in a cooling circuit.

[0093] For example, the rotary output member 5 is associated with a flap to selectively take an open or closed position for the circulation of a fluid in a valve.

[0094] The rotary output member 5 is arranged to provide an actuating torque for, for example, actuating the valve flap.

[0095] This rotating member 5 is rotatable relative to the housing 8 along an axis of rotation XR and comprises a first part 14 and a second part 15 assembled together.

[0096] The housing 8 is provided with two opposing axial stops 17 and 18 on each of which each part 14; 15 of the rotary output member 5 bears respectively so that once assembled and bearing on the axial stops 17; 18 of the housing, the rotary output member 5 is kept axially fixed in the direction of the axis of rotation XR.

[0097] The first and second parts 14; 15 of the rotary member 5 sandwich the axial stops 17; 18 of the housing 8.

[0098] As illustrated in Figure 6, the first part 14 of the rotary output member 5 comprises a toothed wheel 19 configured to cooperate with a toothed wheel 6 of the gear train 3.

[0099] The diameter of this toothed wheel 19 corresponding to the maximum diameter of the rotary output member 5, this diameter being measured perpendicular to the axis of rotation XR.

[0100] The second part 15 of the rotary output member 5 comprises a female socket 20 formed by a cavity, arranged to cooperate with a valve actuating member such as a flap, not shown.

[0101] As can be seen in Figure 4, the cavity 20 has a petal-shaped cross-section, arranged to receive, for example, a rod of complementary shape to the valve flap actuating member.

[0102] The second part 15 is arranged to rotate in a circular outlet opening 21 of the housing 8, thus forming a pivot connection between this second part 15 and the housing 8.

[0103] The second part 15 extends through this outlet opening 21, as illustrated in Figure 5.

[0104] This second part 15 is arranged to rotate in contact with an internal wall 22 of this outlet opening 21.

[0105] The housing 8, with its outlet opening 21, thus forms a smooth bearing for the rotating member 5.

[0106] Thanks to the invention, only one plain bearing is needed to perform the pivot function, which reduces frictional wear.

[0107] The second part 15 of the rotary output member 5 comprises a cylindrical barrel 24 engaged in the output opening 21.

[0108] The housing 8 comprises an internal annular wall 25 provided with a free end 26, which free end 26, in the form of a plate, forms the axial stop 17. This annular wall 25 is said to be internal because it is inside the housing 8.

[0109] This internal annular wall 25 comprises, over a portion of the height, a radially internal chamfer 27 adjacent to the free end 26.

[0110] The toothed wheel 19 of the rotary output member 5 is in axial abutment on this free end 26.

[0111] This internal annular wall 25 surrounds the outlet opening 21 of the housing 8, and has a cylindrical shape of circular section, concentric with the barrel 24 of the second part 15.

[0112] This internal annular wall 25 is made in one piece with the rest of the housing 8.

[0113] The housing 8 further comprises an external annular wall 28 provided with a free end 29, and this free end 29, in the form of a plate, defines the other axial stop 18. This annular wall 28 is said to be external because it is outside the housing 8.

[0114] The cylindrical barrel 24 of the second part 15 comprises an annular collar 30, in axial abutment on this free end 29.

[0115] The external annular wall 28 surrounds the outlet opening 21 of the housing 8, and has a cylindrical shape of circular section, concentric with the barrel 24 of the second part 15 of the rotary outlet member.

[0116] This external annular wall 28 forming an axial stop is made in one piece with the rest of the housing 8.

[0117] The inner diameter of the outer annular wall 28 is smaller than the inner diameter of the inner annular wall 25.

[0118] The actuator 1 comprises an annular seal 33 bearing on a periphery of the second part 15 of the rotary member 5, to provide a seal opposite the outlet opening 21.

[0119] This seal 33 comprises an annular lip 34 in sealed support on the cylindrical barrel 24 of the second part 15, and a rim 35 in sealed support on an internal face of the housing 8.

[0120] The seal 33 has a U-shaped cross-section resting on the internal annular wall 25.

[0121] The seal 33 is inserted into an annular housing 36 defined between the internal annular wall 25 of the housing 8 and the toothed wheel 19 of the rotary output member 5.

[0122] The seal 33, which is an added part, is made of silicone or rubber.

[0123] The rotary output member 5 carries a magnet 38 participating in the operation of the angular position sensor.

[0124] The first and second parts 14, 15 of the rotary output member 5 are produced as two single-piece parts.

[0125] In the example described, the first and second parts 14, 15 of the rotary output member 5 are welded together, by laser welding or by ultrasonic welding or by friction welding.

[0126] The first part 14 of the rotary output member 5 comprises a female shape defined by an annular groove 38 and the second part 15 of the rotary member comprises a male shape defined by an axial crown 39, inserting into the annular groove 38 of the first part 14, as best seen in [Figure 6] and [Figure 7].

[0127] The free end of the crown 39 is chamfered.

[0128] The cylindrical barrel 24 is closed by a transverse wall 40 and the crown 39 is connected to this transverse wall 40.

[0129] This transverse wall 40 comprises an annular shoulder 41 on which the toothed wheel 19 of the first part 14 rests.

[0130] The first part 14 of the rotating member 5 comprises a hollow column 42 connecting to the toothed wheel 19, and this hollow column 42 comprises a housing for housing the magnet 38.

[0131] In another exemplary implementation of the invention, described with reference to [Figure 8] and [Figure 9], the first and second parts 50 and 51 of the rotary output member 52 are assembled together by snap-fastening.

[0132] The characteristics of this embodiment, which are identical or very similar to the example described previously, are not detailed below.

[0133] The second part 51 of the rotary member 52 comprises four snap-fastening tabs 54 arranged to retain the first part 50 on a shoulder 55 of this second part 51.

[0134] After snap-fastening, the rotary member 52 rests on the two opposing axial stops 17, 18 as described above.

[0135] The snap-on tabs 54 rest on the toothed wheel 19 of this first part 50 of the rotating member 52.

[0136] These snap-on tabs 54 are arranged along a circular circumference, and are symmetrical to each other by rotation.

[0137] The second part 51 of the rotary member 52 comprises a retaining groove 57 in which the toothed wheel 19 of the first part 50 of the rotary member 52 is inserted, after passing through the snap-fastening tabs 54.

[0138] The first part 50 of the rotary member 52 further comprises a hollow column 58 connecting to the toothed wheel 19, this hollow column 58 comprising windows 59 in each of which a snap-on tab head 54 engages.

[0139] The windows 59 are arranged adjacent to the gear wheel 19, and are arranged on a circular periphery.

[0140] The second part 51 comprises, at one of its ends, a collar 60 resting on a shoulder 61 of an external annular wall 62 of the housing, so as to define the axial stop 18 within the meaning of the invention.

[0141] In the examples described above, the first and second parts of the rotary output member 5 or 52 are assembled in such a way that once assembled and bearing on the axial stops 17, 18 of the housing, the rotary output member 5 or 52 is kept axially fixed in the direction of the axis of rotation XR.

Claims

Claims

1. Actuator (1) comprising a housing (8), a rotary output member (5; 52) arranged to provide an actuating torque, this rotary member being rotatable relative to the housing (8) along an axis of rotation (XR) and comprising a first part (14; 50) and a second part (15; 51) assembled together, the housing (8) being provided with two opposing axial stops (17, 18) on each of which each part of the rotary output member bears respectively so that once assembled and bearing on the axial stops (17, 18) of the housing, the rotary output member is kept axially fixed in the direction of the axis of rotation (XR).

2. Actuator (1) according to the preceding claim, wherein the first (14; 50) and second (15; 51) parts of the rotary member sandwich the axial stops of the housing.

3. Actuator (1) according to one of the preceding claims, in which the first part (14; 50) of the rotary output member comprises a toothed sector, in particular in the form of a toothed wheel (19), configured to cooperate with a complementary gear element.

4. Actuator (1) according to one of the preceding claims, in which the second part (15; 51) of the rotary output member comprises a male or female socket (20), arranged to cooperate with an actuating member, in particular of the type arranged to perform a valve function.

5. Actuator (1) according to one of the preceding claims, in which the second part (15; 51) is arranged to rotate in an outlet opening (21), in particular circular, of the housing, thus forming a pivot connection between this second part (15; 51) and the housing (8).

6. Actuator (1) according to one of the preceding claims, in which the housing comprises an internal annular wall (25) provided with a free end (26), which free end forms one of the axial stops (17).

7. Actuator (1) according to one of the preceding claims, in which the housing comprises an external annular wall (28) provided with a free end or a shoulder, this free end or this shoulder forming the other of the axial stops (18).

8. Actuator (1) according to one of the preceding claims, in which the actuator comprises a seal (33), in particular an annular seal, bearing on a periphery of the second part of the rotary member, to provide a seal opposite an outlet opening (21) of the housing.

9. Actuator (1) according to one of the preceding claims, wherein the first (14) and second (15) parts of the rotary output member are welded together, in particular by laser welding or by ultrasonic welding or by friction welding.

10. Actuator (1) according to one of claims 1 to 8, in which the first (50) and second (51) parts of the rotary output member are assembled together by snap-fastening.

11. Actuator (1) according to one of the preceding claims, in which at least one of the first and second parts of the rotary output member comprises snap-fastening shapes, in particular in the form of snap-fastening tabs (54), cooperating with the other of the first and second parts.

12. A method of manufacturing an actuator (1), the method comprising the following steps, i) providing a housing (8), ii) providing a rotary output member (5; 52) arranged to provide an actuating torque, this rotary member being rotatable relative to the housing along an axis of rotation (XR) and comprising a first and a second part assembled together, the housing being provided with two opposing axial stops on each of which each part of the member bears respectively, iii) assembling the first (14; 50) and second (15; 51) parts of the rotary output member only once assembled and bearing on the axial stops of the housing, the rotary output member is kept axially fixed in the direction of the axis of rotation (XR).

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