CN119731453A - Actuator, in particular of the electromechanical type - Google Patents

Abstract

The invention relates to an actuator (1) comprising a housing (8) and a rotary output member (5), the rotary output member (5) being arranged to provide an actuation torque, the rotary member being rotatable relative to the housing (8) about a rotational axis (XR) and comprising a first portion (14) and a second portion (15) assembled together, the housing (8) being provided with two opposite axial stops (17, 18), each portion of the rotary output member being supported on each axial stop respectively, such that once assembled and supported on the axial stops (17, 18) of the housing, the rotary output member remains axially stationary in the direction of the rotational axis (XR).

Description

Actuator, in particular of the electromechanical type

Technical Field

The present invention relates to an actuator, in particular of the electromechanical type, in particular for applications on vehicles, such as motor vehicles.

The vehicle may be a land vehicle, an offshore vehicle or an air vehicle.

Background

An electromechanical actuator with an electric motor of the brushless dc motor type is known from patent application DE102020120241 A1. The acronym BLDC motor for such motors represents a brushless dc motor. The actuator acts as a flap actuator in the valve. For control and monitoring purposes, the electric motor of the actuator may be equipped with sensors in order to determine motor parameters, such as the position of the rotor, the speed of the rotor, or the angle of rotation of the actuator element coupled to the rotor.

The actuator described in this patent application DE102020120241A1 comprises, in a housing closed by a cover, an electric motor of the BLDC type having a stator and a rotor. A reduction gear train is also provided to transfer torque generated by the motor to the output pinion. The output pinion is formed in one piece with a hollow shaft passing through an opening in the housing for connection to the valve element. The three-branch support member holds the upper end of the output pinion.

An actuator 100 of a substantially similar type to that described in patent application DE102020120241A1 is depicted in fig. 1. The actuator includes an electric motor 101 that drives an output pinion 102 via a gear train (not shown). The pinion 102 includes a gear 103 and a hollow shaft 104, which are manufactured as one piece. The upper part of the pinion 102 is held in place by a support member 106, the support member 106 forming a first sliding journal bearing 107 for pivoting. A second bearing 108 for pivoting is present at the lower end of the hollow shaft 104. These bearings 107 and 108 are radial type supports. An axial thrust stop is provided between the output pinion 102 and the annular wall 110 of the housing. Aligning the one-piece component (output pinion/hollow shaft) in the two bearings 107 and 108 requires high precision in the size and positioning of these bearings. This requires strict manufacturing tolerances. Furthermore, the one-piece part pivots in the two bearings 107 and 108, and thus pivots at two locations, resulting in a greater amount of wear. Furthermore, the presence of a hall effect sensor above the magnet carried by the one-piece component (output pinion/hollow shaft) requires the use of a support member 106.

The invention particularly seeks to improve an actuator of the type described with reference to figure 1.

Disclosure of Invention

The invention thus relates to an actuator comprising a housing, a rotary output member arranged in such a way as to provide an actuation torque, the rotary output member being rotatable relative to the housing about a rotational axis and comprising a first portion and a second portion assembled together, the housing being provided with two opposite axial thrust stops, each portion of the rotary output member being supported on a respective axial thrust stop, such that once assembled and supported on the axial thrust stop of the housing, the rotary output member remains axially stationary in the direction of the rotational axis.

An axial thrust stop refers to a thrust stop that is capable of blocking translational movement of a rotating member in one of the directions along the rotational axis.

Thus, according to the invention, one of the axial thrust stops blocks translational movement in one of the two directions along the rotation axis, while the other one of the axial thrust stops blocks translational movement in the opposite direction along the rotation axis. These opposing axial stops thus axially fix the rotary output member along its axis of rotation, which member cannot achieve translational movement along its axis of rotation in one direction or the other.

Thus, the rotary output member is able to rotate about its axis of rotation without effecting translational movement along that axis.

By the invention, blocking of translational movement along the rotation axis of the rotating member can be achieved simply by assembling the first and second portions on the axial thrust stop. For example, no additional components need be used, such as the support member 104 in the actuator of fig. 1.

According to one aspect of the invention, the first and second portions of the rotating member sandwich an axial thrust stop of the housing.

According to one aspect of the invention, the first portion of the rotary output member comprises a toothed sector, in particular in the form of a gear, configured to cooperate with a complementary gear element. The complementary gear element forms in particular part of a gear train between the electric motor and the rotary output member.

According to one aspect of the invention, the diameter of the toothed sector, in particular the diameter of the gear wheel, corresponds to the maximum diameter of the rotary output member, measured perpendicular to the axis of rotation.

According to one aspect of the invention, the second part of the rotary output member comprises a male or female plug-in connector designed to cooperate with the actuating member, in particular of the type designed to perform a valve function.

According to one aspect of the invention, an actuating member is associated with the shutter for selectively adopting an open or closed position for fluid flow through the valve.

According to one aspect of the invention, the second portion of the rotary output member comprises a female plug connector formed by a cavity configured to cooperate with the actuation member to transmit actuation torque thereto.

According to one aspect of the invention, the cavity has a substantially polygonal cross-section, for example a hexagonal or octagonal cross-section, or a lobed cross-section, designed to receive a correspondingly shaped rod of the actuation member.

According to one aspect of the invention, the second part is designed to rotate in an output opening of the housing, in particular a circular opening, whereby a pivot connection is formed between the second part and the housing.

According to one aspect of the invention, the second portion of the rotary output member extends through the output opening.

According to one aspect of the invention, the second part is designed to rotate in contact with the inner wall of the outlet opening of the housing.

According to one aspect of the invention, the housing and its output opening thus form a sliding journal bearing for the second part of the rotating member.

Thanks to the invention, a single sliding journal bearing is required to perform the pivoting function, reducing the frictional wear.

Furthermore, the invention allows for wider tolerances in the dimensions of the components during manufacture due to the single bearing.

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

According to one aspect of the invention, the housing comprises an inner annular wall provided with a free end forming one of the axial thrust stops. The annular wall is referred to as internal because it is on the inside of the housing. The housing is in particular closed by a cover, for example a substantially planar cover.

According to one aspect of the invention, the free end is a flat portion. The flat forms one of the axial thrust stops.

According to one aspect of the invention, the inner annular wall includes a chamfer radially inward and adjacent the free end at a portion of its height.

According to one aspect of the invention, the toothed sector of the rotary output member, in particular the gear wheel, axially abuts the free end.

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

According to one aspect of the invention, the inner annular wall forming an axial thrust surrounds the output opening of the housing.

According to one aspect of the invention, the inner annular wall forming the axial thrust stop is cylindrical with a circular cross section.

According to one aspect of the invention, the inner annular wall forming the axial thrust stop is concentric with the barrel of the second portion of the rotary output member.

According to one aspect of the invention, the inner annular wall forming the axial thrust is made in one piece with the rest of the housing.

According to one aspect of the invention, the housing comprises an outer annular wall provided with a free end or shoulder forming the other of the axial thrust stops. The annular wall is referred to as external because it is on the outside of the housing.

Thus, one of the axial thrust stops is inside the housing and the other of the axial thrust stops is outside the housing.

According to one aspect of the invention, the free end of the outer annular wall is a flat portion.

According to one aspect of the invention, the second part of the rotary output member, in particular the cylindrical barrel of the second part, comprises a flange, in particular an annular flange, which axially abuts the free end or an annular shoulder of the outer annular wall of the housing.

According to one aspect of the invention, the outer annular wall forming an axial thrust stop surrounds the output opening of the housing.

According to one aspect of the invention, the outer annular wall forming the axial thrust stop is cylindrical with a circular cross section.

According to one aspect of the invention, the outer annular wall forming the axial thrust stop is concentric with the barrel of the second portion of the rotary output member.

According to one aspect of the invention, the outer annular wall forming the axial thrust is made in one piece with the rest of the housing.

According to one aspect of the invention, the inner diameter of the outer annular wall is smaller than the inner diameter of the inner annular wall forming the axial thrust stop.

According to one aspect of the invention, the actuator comprises a seal, in particular an annular seal, which is supported against the periphery of the second part of the rotating member so as to seal against the output opening.

According to one aspect of the invention, the seal comprises an annular lip that is supported in a fluid-tight manner against the cylindrical barrel of the second portion of the rotary output member.

According to one aspect of the invention, the seal further comprises an edge pressed against the inner face of the housing in a fluid-tight manner.

According to one aspect of the invention, the seal has a U-shaped cross section, pressing against an inner annular wall forming an axial thrust stop.

According to one aspect of the invention, a seal is inserted in an annular space defined between an inner annular wall of the housing and the gear of the rotary output member.

According to one aspect of the invention, the seal as an additional component is made in particular of silicone or rubber.

According to one aspect of the invention, the rotary output member supports a magnet that facilitates operation of the angular position sensor.

According to one aspect of the invention, at least one, and preferably both, of the first and second portions of the rotary output member are parts manufactured as one piece.

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

According to one aspect of the invention, the first and second portions of the rotary output member have male and female shapes, respectively, that can be assembled with each other, and these shapes are welded together.

According to one aspect of the invention, the first portion of the rotary output member comprises a concave shape defined by an annular groove, and the second portion of the rotary member comprises a convex shape defined by an axial ring which can be inserted into the annular groove of the first portion.

According to one aspect of the invention, the second portion of the rotating member comprises a cylindrical barrel closed by a transverse wall, and the ring is connected to the transverse wall.

According to one aspect of the invention, the free end of the ring is chamfered.

According to one aspect of the invention, the second part of the rotating member comprises a shoulder, in particular an annular shoulder, against which the gear of the first part bears.

According to one aspect of the invention, the first part of the rotating member comprises a hollow column connected to the gear, the hollow column comprising a space for housing a magnet of a position sensor, in particular of the hall effect type.

According to another aspect of the invention, the first and second portions of the rotary output member are assembled together by snap fastening.

According to one aspect of the invention, at least one of the first and second portions of the rotary output member comprises a snap-fastening shape cooperating with the other of the first and second portions, in particular in the form of a snap-fastening tab.

According to one aspect of the invention, the second portion of the rotating member includes a snap-fastening tab designed to retain the first portion of the rotating member on a shoulder of the second portion.

After snap fastening, the rotating member is supported against two opposite axial thrust stops.

According to one aspect of the invention, the snap-fastening tabs bear against the gear of the first portion of the rotating member.

According to one aspect of the invention, the snap-fastening tabs are arranged on a circular periphery.

According to one aspect of the invention, the tabs are rotationally symmetric with respect to each other. Alternatively, the tabs may have different shapes from each other.

According to one aspect of the invention, the number of snap-fastening tabs is four.

According to one aspect of the invention, the second portion of the rotating member includes a retaining groove into which the gear of the first portion of the rotating member is inserted once the snap-fastening tab is overcome.

According to one aspect of the invention, the first portion of the rotating member comprises a gear and a hollow post connected to the gear, the hollow post comprising apertures, each aperture having a pointed end of a snap-fastening tab engaged therein.

According to one aspect of the invention, the aperture is adjacent the gear.

According to one aspect of the invention, the aperture is located on the circular perimeter.

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

According to one aspect of the invention, the actuator comprises an electric motor and a gear train actuatable by the electric motor for transmitting torque to the rotary output member.

According to one aspect of the invention, the actuator comprises an electronic board supporting an angular position sensor for detecting the angular position of the rotary output member.

According to one aspect of the invention, the actuator is associated with a valve for guiding the heat transfer fluid in the cooling circuit, or with a check valve for the heat transfer fluid in the cooling circuit, or with a throttle valve for the heat transfer fluid in the cooling circuit.

The invention relates to a method for manufacturing an actuator, comprising the steps of i) providing a housing, ii) providing a rotary output member arranged in such a way as to generate an actuation torque, the rotary output member being rotatable relative to the housing about a rotational axis and comprising a first part and a second part assembled together, the housing being provided with two opposite axial thrust stops, each part of the member bearing on a respective axial thrust stop, iii) assembling the first part and the second part of the rotary output member such that, once assembled and bearing on the axial thrust stops of the housing, the rotary output member remains axially stationary in the direction of the rotational axis.

According to one aspect of the invention, assembly is achieved by welding together the first and second portions of the rotary output member.

According to one aspect of the invention, assembly is achieved by snap fastening together the first and second portions of the rotary output member.

Drawings

Other features and advantages of the invention will become more apparent upon reading the following description, given by way of illustrative and non-limiting example, and with reference to the accompanying drawings in which:

FIG. 1 schematically and partially illustrates a cross-section of an actuator not relevant to the present invention;

FIG. 2 schematically and partially illustrates a perspective view of an actuator according to an exemplary embodiment of the invention;

FIG. 3 schematically and partially illustrates a perspective view of the actuator of FIG. 2, without the cover;

FIG. 4 schematically and partially illustrates one face of the actuator of FIG. 2;

FIG. 5 schematically and partially illustrates a cross-section of the actuator of FIG. 2 at V-V;

FIG. 6 schematically and partially illustrates a perspective view of a first portion of a rotating member of the actuator of FIG. 2;

FIG. 7 schematically and partially illustrates a perspective view of a second portion of a rotating member of the actuator of FIG. 2;

FIG. 8 schematically and partially illustrates a cross-section of an actuator according to an exemplary embodiment of the invention;

fig. 9 schematically and partially shows a perspective view of a first portion of a rotating member of the actuator of fig. 8.

Detailed Description

Fig. 2 to 7 show an actuator 1 of the electromechanical type, comprising an electric motor 2 of the BLDC type, for example, and a gear train 3 of the reduction gear train type, which gear train 3 can be actuated by an output pinion 4 of the electric motor 2 in order to transmit torque to a rotary output member 5.

The gear train 3 comprises, in a known manner, a plurality of gears 6 of different diameters.

The actuator 1 comprises a housing 8 closed by a substantially planar cover 9, in this case both made of plastic. The housing 8 comprises, in a manner known per se, an electrical connection socket 7, which electrical connection socket 7 is designed to mate with an electrical connector (not shown).

The actuator 1 further comprises an electronic board 10, the electronic board 10 supporting an angular position sensor 11 of the hall effect type for detecting the angular position of the rotary output member 5, as clearly visible in fig. 5.

The actuator 1 may be associated with a valve for guiding the heat transfer fluid in the cooling circuit, or with a check valve for the heat transfer fluid in the cooling circuit, or with a throttle valve for the heat transfer fluid in the cooling circuit.

For example, the rotary output member 5 is associated with a shutter for selectively adopting an open or closed position for fluid flow through the valve.

The rotary output member 5 is designed to provide an actuation torque for e.g. actuating a valve flap.

The rotating member 5 is rotatable relative to the housing 8 about an axis of rotation XR and comprises a first part 14 and a second part 15 assembled together.

The housing 8 is provided with two opposite axial thrust stops 17 and 18 on each of which each portion 14;15 of the rotary output member 5 is supported, respectively, so that once assembled and supported on the axial thrust stops 17;18 of the housing, the rotary output member 5 remains axially stationary in the direction of the rotation axis XR.

The first and second portions 14, 15 of the rotary member 5 sandwich the axial thrust stops 17, 18 of the housing 8.

As shown in fig. 6, the first portion 14 of the rotary output member 5 includes a gear 19, which gear 19 is configured to cooperate with the gear 6 of the gear train 3.

The diameter of this gear wheel 19 corresponds to the maximum diameter of the rotary output member 5, measured perpendicular to the axis of rotation XR.

The second portion 15 of the rotary output member 5 comprises a female plug connector 20 formed by a cavity configured to cooperate with a valve actuating member (e.g. a shutter not shown).

As can be seen in fig. 4, the cavity 20 has a lobed cross-section designed to receive a correspondingly shaped stem of, for example, a valve actuating member.

The second part 15 is designed to rotate in the circular output opening 21 of the housing 8, thereby forming a pivotal connection between the second part 15 and the housing 8.

As shown in fig. 5, the second portion 15 extends through the output opening 21.

The second portion 15 is designed to rotate in contact with the inner wall 22 of the output opening 21.

Thus, the housing 8 and its output opening 21 form a sliding journal bearing for the rotating member 5.

Thanks to the invention, only a single journal bearing is needed to perform the pivoting function, thereby reducing frictional wear.

The second portion 15 of the rotary output member 5 comprises a cylindrical barrel 24 engaged in the output opening 21.

The housing 8 comprises an inner annular wall 25 provided with a free end 26, which free end 26 is in the form of a flat portion forming the axial thrust stop 17. The annular wall 25 is referred to as internal because it is on the inside of the housing 8.

The inner annular wall 25 comprises, over part of its height, a chamfer 27 radially inside and adjacent to the free end 26.

The gear wheel 19 of the rotary output member 5 axially abuts this free end 26.

The inner annular wall 25 surrounds the outlet opening 21 of the housing 8 and has a cylindrical shape of circular cross section, concentric with the barrel 24 of the second portion 15.

The inner annular wall 25 is made in one piece with the rest of the housing 8.

The housing 8 further comprises an outer annular wall 28 provided with a free end 29, which free end 29 is in the form of a flat portion forming the other axial thrust stop 18. The annular wall 28 is referred to as external because it is on the outside of the housing 8.

The cylindrical barrel 24 of the second portion 15 includes an annular flange 30 axially abutting the free end 29.

An outer annular wall 28 surrounds the output opening 21 of the housing 8 and has a cylindrical shape of circular cross section concentric with the barrel 24 of the second portion 15 of the rotary output member.

The outer annular wall 28 forming an axial thrust is made in one piece with the rest of the housing 8.

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

The actuator 1 comprises an annular seal 33, which annular seal 33 bears against the periphery of the second portion 15 of the rotating member 5 so as to seal against the output opening 21.

The seal 33 comprises an annular lip 34 of the cylindrical barrel 24 bearing in fluidtight manner against the second portion 15, and an edge 35 pressing in fluidtight manner against the inner face of the housing 8.

The seal 33 has a U-shaped cross-section pressing against the inner annular wall 25.

The seal 33 is inserted in an annular space 36 defined between the inner annular wall 25 of the housing 8 and the gear wheel 19 of the rotary output member 5.

The seal 33 as an additional member is made of silicone or rubber.

The rotary output member 5 supports a magnet 38, which magnet 38 facilitates the operation of the angular position sensor.

The first portion 14 and the second portion 15 of the rotary output member 5 are manufactured as two one-piece parts.

In the example described, the first portion 14 and the second portion 15 of the rotary output member 5 are welded together using laser welding or ultrasonic welding or friction welding.

The first portion 14 of the rotary output member 5 comprises a concave shape defined by an annular groove, while the second portion 15 of the rotary member comprises a convex shape defined by an axial ring 39, which axial ring 39 can be inserted into the annular groove of the first portion 14, as best seen in fig. 6 and 7.

The free end of the ring 39 is chamfered.

The cylindrical drum 24 is closed by a transverse wall 40, to which transverse wall 40 a ring 39 is connected.

The transverse wall 40 comprises an annular shoulder 41 against which the gear 19 of the first part 14 bears.

The first part 14 of the rotating member 5 comprises a hollow post 42 connected to the gear wheel 19, which hollow post 42 comprises a space for accommodating the magnet 38.

In another embodiment of the invention described with reference to fig. 8 and 9, the first and second portions 50, 51 of the rotary output member 52 are assembled together by snap fastening.

Those features of this embodiment that are the same or very similar to the previous embodiment will not be described in detail below.

The second portion 51 of the rotary member 52 comprises four snap-fastening tabs 54 designed to hold the first portion 50 on a shoulder 55 of the second portion 51.

After snap fastening, the rotary member 52 is supported against the two opposite axial thrust stops 17, 18, as described above.

The snap-fastening tab 54 bears against the gear 19 of the first portion 50 of the rotary member 52.

The snap fastening tabs 54 are arranged on the circular periphery and are rotationally symmetrical to each other.

The second portion 51 of the rotating member 52 comprises a retaining groove 57 into which retaining groove 57 the gear 19 of the first portion 50 of the rotating member 52 is inserted once the snap-fastening tab 54 is overcome.

The first portion 50 of the rotary member 52 further comprises a hollow post 58 connected to the gear 19, the hollow post 58 comprising apertures 59, in each aperture 59 engaging the tip of the snap fastening tab 54.

The aperture 59 is located near the gear 19 and is arranged on the circular periphery.

The second portion 51 comprises a flange 60 at one end thereof, said flange 60 abutting against a shoulder 61 of an outer annular wall 62 of the housing so as to define the axial thrust stop 18 within the meaning of the present invention.

In the above example, the first and second portions of the rotary output member 5 or 52 are assembled in such a way that once assembled and supported on the axial thrust stops 17, 18 of the housing, the rotary output member 5 or 52 remains axially stationary in the direction of the rotation axis XR.

Claims (12)

1. An actuator (1) comprising a housing (8), a rotary output member (5; 52), the rotary output member (5; 52) being arranged in such a way as to provide an actuation torque, the rotary member being rotatable relative to the housing (8) about a rotational axis (XR) and comprising a first portion (14; 50) and a second portion (15; 51) assembled together, the housing (8) being provided with two opposite axial thrust stops (17, 18), each portion of the rotary output member being supported on a respective axial thrust stop, such that, once assembled and supported on the axial thrust stops (17, 18) of the housing, the rotary output member remains axially stationary in the direction of the rotational axis (XR).

2. Actuator (1) according to claim 1, wherein the first portion (14; 50) and the second portion (15; 51) of the rotating member sandwich the axial thrust stop of the housing.

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

4. Actuator (1) according to any of the preceding claims, wherein the second portion (15; 51) of the rotary output member comprises a male or female plug-in connector (20) designed to cooperate with an actuating member, in particular of the type designed to perform a valve function.

5. Actuator (1) according to any of the preceding claims, wherein the second part (15; 51) is designed to rotate in an output opening (21) of the housing, in particular a circular opening, whereby a pivot connection is formed between the second part (15; 51) and the housing (8).

6. Actuator (1) according to any of the preceding claims, wherein the housing comprises an inner annular wall (25) provided with a free end (26) forming one of the axial thrust stops (17).

7. Actuator (1) according to any of the preceding claims, wherein the housing comprises an outer annular wall (28) provided with a free end or shoulder forming the other of the axial thrust stops (18).

8. Actuator (1) according to any of the preceding claims, wherein the actuator comprises a seal (33), in particular an annular seal, which is supported against the periphery of the second part of the rotating member so as to seal against the output opening (21) of the housing.

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

10. Actuator (1) according to any of claims 1 to 8, wherein the first portion (50) and the second portion (51) of the rotary output member are assembled together by means of snap fastening.

11. Actuator (1) according to any of the preceding claims, wherein at least one of the first and second portions of the rotary output member comprises a snap-fastening shape cooperating with the other of the first and second portions, in particular in the form of a snap-fastening tab (54).

12. A method for manufacturing an actuator (1) comprises the steps of i) providing a housing (8), ii) providing a rotary output member (5; 52), the rotary output member (5; 52) being arranged in such a way as to provide an actuation torque, the rotary member being rotatable relative to the housing about a rotational axis (XR) and comprising a first portion and a second portion assembled together, the housing being provided with two opposite axial thrust stops, each portion of the member bearing on a respective axial thrust stop, iii) assembling the first portion (14; 50) and the second portion (15; 51) of the rotary member such that, once assembled and bearing on the axial thrust stop of the housing, the rotary output member remains axially stationary in the direction of the rotational axis (XR).