Actuator

Abstract

The present invention relates to an actuator (1) comprising a housing (2) defining a motor volume in which an electric motor (10) is received, a torque output element (16), a separating wall (20) closing the motor volume of the housing (2), a circuit board (40) arranged on the separating wall (20) on the side opposite the motor volume, the circuit board comprising connection holes, a cover (5) fastened to the housing (2) and defining, with the separating wall (20), an electronic volume in which the circuit board (40) is located, an electrical connector (30) comprising conductive tracks (35) able to be inserted into the connection holes of the circuit board (40); according to the invention, the separating wall (20) comprises a first means (25) for centering the circuit board (40) and a second means (26) for centering the electronic connector (30).

Description

[0001] Description

[0002] Title of the invention: Actuator

[0003] [1] The invention relates to an actuator, in particular an electromechanical actuator.

[0004] [2] The actuator according to the invention is of particular interest in the field of motor vehicles and is more specifically applicable to the field of transmissions. For example, such an actuator according to the invention may be suitable for a parking lock system for a vehicle transmission, a clutch connection / disconnection system, a fluid pump system, a transmission gear shifting system, etc.

[0005] [3] The invention applies in particular to actuators comprising a brushless electric motor. This type of motor requires an electronic board, also called a printed circuit board. This electronic board is electrically connected on one side to the stator of the electric motor and on the other to an electrical connector, and carries the electronic components necessary for controlling the electric motor. This electronic board is sensitive to external contamination. It is therefore necessary to protect it from such external contamination.

[0006] [4] Most known actuators comprise a housing defining a motor volume in which an electric motor is housed, a partition wall enclosing the motor volume from the housing, and an electronic circuit board mounted on the partition wall on the side opposite the motor volume, defining an electronic volume. To protect the electronic circuit board from external contamination, it is known to fill the electronic volume with a resin that makes it impermeable to external contamination. Such an actuator is described, for example, in document WO 2017 / 084949 A1.

[0007] [5] The use of resin has a major drawback because in the event of failure of the actuator, it is not possible to separate the resin from the electronic board without damaging the assembly.

[0008] [6] As an alternative to this resin-based solution, it is known to close the electronic enclosure with a lid. In most cases, this lid incorporates the electrical connector. This creates a problem with the electrical connection between the connector and the circuit board because this connection is made blindly during the assembly of the lid onto the housing or support wall. It is therefore impossible to know if the electrical connection between the connector and the circuit board is functional.

[0009] [7] It is therefore necessary to propose an actuator that remedies the problems mentioned above by proposing an actuator that is simple to assemble, simple to repair while ensuring good sealing of the electronic volume but also a reliable electrical connection between the components.

[0010] [8] Thus, the invention provides an actuator comprising a housing defining a motor volume in which an electric motor is housed, a torque output element, a partition wall closing the motor volume of the housing, an electronic board disposed on the partition wall on the side opposite the motor volume, the electronic board including connection holes, a cover that attaches to the housing and, together with the partition wall, defines an electronic volume in which the electronic board is located, and an electrical connector separate from the cover and including conductive tracks adapted to fit into the connection holes of the electronic board. According to the invention, the partition wall includes a first means for centering the electronic board and a second means for centering the electronic connector.

[0011] [9] This invention allows, during actuator assembly, for the precise alignment and insertion of the conductive tracks of the electrical connector with the connection holes of the electronic board without risk of incorrect insertion, particularly bending of the conductive tracks. Centering the electronic board and the electrical connector on the separating wall ensures a common reference frame, minimizing the number of dimensional links between these elements.

[0012]

[0010] Another advantage of the invention is the ability to interchange the electrical connector at a lower cost without redesigning the actuator. Indeed, if the number of conductive tracks were to change depending on the internal components of the actuator, it is possible to change only the electrical connector and not the entire cover.

[0011] The electric motor conventionally comprises a stator, a rotor, and a drive shaft that is rotationally connected to the rotor. The drive shaft extends along an X-axis and defines the axial extension of the actuator. Advantageously, the electric motor is of the brushless type.

[0013]

[0012] The torque output element according to the invention can take the form of different components depending on the actuator application. For example, the torque output element can be a drive pinion, a male or female connector, a hydraulic system such as a pump rotor, or generally any element capable of transmitting torque. The torque output element can be located inside or outside the housing.

[0014]

[0013] According to the invention, the actuator comprises at least one means for fixing the electronic connector to the separating wall. The fixing means is separate from the second centering means.

[0015]

[0014] According to another feature of the invention, the fastening means comprises at least one screw and at least one screw hole disposed in the partition wall. Advantageously, the screw is a self-tapping screw that does not require a tapping step for the screw hole. Conventional screws can also be used. Advantageously, the electrical connector comprises at least one through hole allowing the screw to pass through.

[0016]

[0015] According to the invention, the electrical connector extends through an opening in the cover.

[0017]

[0016] According to the invention, the electrical connector comprises a base portion and a connection portion. Advantageously, the base portion is located within the electronic enclosure and the connection portion is located outside the cover. By definition, the base portion is wider than the connection portion. The connection portion includes a female connector adapted to receive a male connector from an external connector. The conductive tracks are overmolded, particularly at the junction between the base portion and the connection portion.

[0018]

[0017] According to the invention, the base portion includes a sealing means between the base portion of the electrical connector and the cover, the sealing means thus being located within the electronic volume. Advantageously, the base portion of the connector includes a peripheral groove around the connection portion, and the sealing means, which is in the form of a gasket, is disposed in this peripheral groove. Preferably, the gasket is of the four-lobe type.

[0019]

[0018] According to the invention, the first means for centering the electronic board is at least one centering pin received in at least one opening of the electronic board. Advantageously, the at least one centering pin is formed from the same material as the separating wall. In other words, the at least one centering pin is integral with the separating wall.

[0020]

[0019] According to the invention, the second means for centering the electrical connector is at least one centering pin received in at least one opening of the electrical connector. Advantageously, the at least one centering pin is formed from the same material as the separating wall. In other words, the at least one centering pin is integral with the separating wall.

[0021]

[0020] According to an additional feature of the invention, the second means for centering the electrical connector comprises two centering pins received in two openings of the electrical connector.

[0022]

[0021] According to the invention, the two openings have different geometric shapes. The first opening is a cylindrical hole and the second opening is an oblong hole. This feature makes the assembly between the electrical connector and the separating wall isostatic and not hyperstatic.

[0023]

[0022] According to the invention, the housing and the cover are assembled one on top of the other along a joining plane, and the separating wall extends substantially along the joining plane. Advantageously, the separating wall comprises a first sealing means between the separating wall and the housing and a second sealing means between the separating wall and the cover.

[0024] Advantageously, the first and second sealing means are located on either side of the junction plane. Preferably, the two sealing means are two O-rings received in two radial grooves in the separating wall.

[0025]

[0023] Advantageously, the housing and lid are made of metal and the partition wall is made of plastic.

[0024] Other features and advantages of the invention will become apparent from the following detailed embodiment, with reference to the accompanying figures:

[0026]

[0025] [Figure 1] represents a perspective view of an actuator according to the invention;

[0027]

[0026] [Figure 2] represents a cross-sectional view of the actuator of [Figure 3];

[0028]

[0027] [Figure 3] represents a perspective cross-sectional view of the actuator of [Figure 4] focused on the cooperation between the separating wall and the electrical connector;

[0029]

[0028] [Figure 4] represents a top perspective view of the actuator of [Figure 5] without the cover.

[0030]

[0029] It should be noted that the figures disclose the invention in sufficient detail for its implementation, and that the figures help to further define the invention if necessary. However, the invention should not be limited to the embodiment disclosed in the description.

[0031]

[0030] With reference to [Figure 6] an actuator is shown comprising mainly a housing 2 and a cover 3. By definition, the bottom or lower part of the actuator 1 will be the housing 2 and the top or upper part of the actuator 1 will be the cover 3.

[0032]

[0031] A torque output element 16 protrudes downwards from the actuator 1. This torque output element 16 is a drive pinion suitable for coupling to a component of a motor vehicle transmission. The torque output element 16 rotates about the X-axis. This X-axis defines the axial extension of the actuator 1.

[0033]

[0032] An electrical connector 30 protrudes upwards from the actuator 1. This electrical connector 30 is a female connector suitable for coupling to a male connector of a vehicle's on-board electrical system. The electrical connector 30 is separate from the cover 5.

[0034]

[0033] The housing 2 and the cover 5 are assembled one on top of the other along a junction plane P visible in [Figure 2]. The housing 2 and the cover 5 each include a junction portion extending radially with respect to the axial extension of the actuator. The junction portion of the housing 2 includes a plurality of tabs 3 angularly distributed around its periphery. These tabs 3 are folded over the junction portion of the cover 5 once the cover 5 is assembled onto the housing 2. The housing 2 and the cover 5 are made of metal.

[0035]

[0034] The junction portions of the housing 2 and the cover 5 each include a plurality of attachment means 4, in the form of through holes, for fixing the actuator 1 to a support.

[0036]

[0035] Figure 2 shows more precisely the inside of the actuator 1. The cylindrical housing 2 defines a motor volume in which the electric motor 10 is received.

[0037]

[0036] The electric motor 10 is a brushless motor and comprises a stator 11, a rotor 12 and a motor shaft 13 linked in rotation with the rotor 12. The motor shaft 13 extends along the X axis and is guided in rotation by two bearings 14, 15 distributed axially on each side of the electric motor.

[0038]

[0037] The drive shaft 13 includes at one of its axial ends a torque output element 16 which, in the described embodiment, is in the form of a toothed drive pinion. This torque output element 16 is located at a free end of the drive shaft 13, which is outside the housing 2. An opening in the lower part of the housing 2 allows the drive shaft 13 to pass through.

[0039]

[0038] The first bearing 14 is housed in the housing 2 and is located axially between the electric motor 10 and the torque output element 16. A lip seal 17 is also housed in the housing 2 and is located axially between the first bearing 14 and the torque output element 16. This lip seal 17 prevents external contaminants from entering the motor volume of the actuator 1 through the opening in the lower part of the housing 2.

[0040]

[0039] The second bearing 15 is housed in a cylindrical housing in the separating wall 20. This separating wall 20 extends transversely to the axis X and partly along the junction plane P of the housing 2 and the cover 5 and closes the motor volume of the housing 2. The separating wall 20 is made of plastic.

[0041]

[0040] The separating wall 20 includes a first sealing means 21, 22 between the separating wall 20 and the housing 2 and a second sealing means 23, 24 between the separating wall 20 and the cover 5. The first sealing means 21, 22 and the second sealing means 23, 24 are located on each side of the junction plane P. The two sealing means are two O-rings 22, 24 received in two radial grooves 21, 23 of the separating wall 20. The two O-rings 22, 24 provide radial sealing.

[0042]

[0041] The separating wall 20 rests axially against the junction portion of the housing 2. In other words, the junction portion of the housing 2 defines an axial stop for the separating wall 20 by means of a shoulder present on the separating wall 20. This shoulder is located in the junction plane P of the housing 2 and the cover 5.

[0043]

[0042] An electronic board 40 is disposed on the partition wall 20 on the side opposite the motor compartment. The partition wall 20 includes a first centering means 25, in the form of a cylindrical centering pin, for the electronic board 40 on the partition wall 20. In the embodiment of [Figure 2], two cylindrical centering pins are present and are received in two complementary openings in the electronic board 40.

[0044]

[0043] Conductive tracks 19 allowing an electrical link between the electronic board 40 and the stator 11 pass through the support wall 20. These conductive tracks are overmolded onto the support wall 20 so as to guarantee sealing on both sides of the separating wall.

[0045]

[0044] The electronic card 40 rests on an axial shoulder present on the separating wall 20.

[0046]

[0045] The electronic card 40 further includes electrical connection holes into which conductive tracks 35 of the electrical connector 30 are inserted once the electrical connector 30 is assembled on the separating wall 20.

[0047]

[0046] The cover 5 is attached to the housing 2 as described above and defines with the separating wall 20 an electronic volume in which the electronic board 40 is located.

[0048]

[0047] A magnetic target 18 is fixed to the end of the motor shaft 13 opposite the end where the torque output element 16 is located. The separating wall includes a pocket with a shape complementary to the magnetic target 18. The magnetic target 18 faces a sensor (not shown) arranged on the electronic board 40 and allows the angular position of the motor shaft 13 to be detected. The magnetic target 18 and the sensor are located on opposite sides of the separating wall.

[0049]

[0048] As seen in [Figure 2], the electrical connector 30 extends axially through an opening 6 in the cover 5. The electrical connector 30 comprises a base portion 33 and a connection portion 34. The base portion 33 is located within the electronic volume and the connection portion 34 is located outside the cover 5.

[0050]

[0049] The base portion 33 includes a sealing means 31 between the base portion 33 of the electrical connector 30 and the cover 5. The sealing means 31 is located within the electronic compartment. The base portion 33 of the electrical connector 30 includes a peripheral groove around the connection portion 34, and the sealing means, which is in the form of a four-lobe seal, is disposed in this peripheral groove. This seal 21 prevents external contaminants from entering the electronic compartment of the actuator 1 through the opening 6 in the upper part of the cover 5. This seal 21 provides axial sealing.

[0051]

[0050] Figure 3 shows more precisely the cooperation between the electrical connector 30 and the support wall 20.

[0052]

[0051] The separating wall 20 includes a second centering means 26, in the form of a cylindrical centering pin, for the electrical connector 30 on the separating wall 20. In the embodiment shown in [Figure 3], two cylindrical centering pins 26 are present and are received in two complementary openings 32, 36 of the electrical connector. The two openings 32, 36 have different geometric shapes. The first opening 32 is a cylindrical hole and the second opening 36 is an oblong hole. The two cylindrical centering pins 26 thus position the electrical connector 30 isostatically on the separating wall 20, ensuring optimal alignment and insertion of the conductive tracks 35 into the connection holes of the electronic board 40.

[0053]

[0052] Figure 4 shows the attachment of the electrical connector 30 to the support wall 20. The electrical connector 30 is fixed by two screws 32, in particular two self-tapping screws, which are inserted into two shafts of the partition wall 20, each of which has a screw hole. The electrical connector 30 has two through holes allowing the passage of the two screws 32.

[0054]

[0053] Also visible on this [Figure 4] are the cylindrical centering pins 25 allowing the electronic board 40 to be centered on the separating wall 20.

[0055]

[0054] Although the invention has been described in connection with a particular embodiment, it is clearly evident that it is by no means limited to it and that it includes all technical equivalents of the means described.

[0056]

[0055] In the claims, the reference symbols in parentheses shall not be interpreted as a limitation of the claim.

Claims

Demands

1. Actuator (1) comprising a housing (2) defining a motor volume in which an electric motor (10) is received, a torque output element (16), a partition wall (20) closing the motor volume of the housing (2), an electronic board (40) disposed on the partition wall (20) on the side opposite the motor volume, the electronic board (40) comprising connection holes, a cover (5) attaching to the housing (2) and defining with the partition wall (20) an electronic volume in which the electronic board (40) is located, an electrical connector (30) separate from the cover (5) and comprising conductive tracks (35) adapted to fit into the connection holes of the electronic board (40), characterized in that the partition wall (20) comprises a first centering means (25) of the electronic board (40) and a second centering means (26) of the electronic connector (30).

2. Actuator (1) according to claim 1, characterized in that it comprises at least one means for fixing (32) the electronic connector (30) on the separating wall (20), the fixing means (32) being distinct from the second centering means (26).

3. Actuator (1) according to claim 2, characterized in that the fastening means (32) comprises at least one screw and at least one screw hole disposed in the separating wall (20).

4. Actuator (1) according to any one of the preceding claims, characterized in that the electrical connector (30) extends through an opening (6) in the cover (5).

5. Actuator (1) according to any one of the preceding claims, characterized in that the electrical connector (30) comprises a base portion (33) and a connection portion (34), the base portion (33) is located in the electronic volume and the connection portion (34) is located outside the cover (5).

6. Actuator (1) according to claim 5, characterized in that the base portion (33) comprises a sealing means (31) between the base portion (33) of the electrical connector (30) and the cover (5), the sealing means (31) is located in the electronic volume.

7. Actuator (1) according to any one of the preceding claims, characterized in that the first centering means (25) of the electronic card (40) is at least one centering pin received in at least one opening of the electronic card (40).

8. Actuator (1) according to any one of the preceding claims, characterized in that the second centering means (26) of the electrical connector (30) is at least one centering pin received in at least one opening of the electrical connector (30).

9. Actuator (1) according to claim 8, characterized in that the second centering means (26) of the electrical connector (30) comprises two centering pins received in two openings (32, 36) of the electrical connector (30).

10. Actuator (1) according to claim 9, characterized in that the two openings (32, 36) are of different shapes, the first opening (32) is a cylindrical hole and the second opening (36) is an oblong hole.

11. An actuator (1) according to any one of the preceding claims, characterized in that the housing (2) and the cover (5) are assembled one on top of the other along a junction plane (P), the separating wall (20) extends substantially and partly along the junction plane (P), the separating wall (20) comprises a first sealing means (21, 22) between the separating wall (20) and the housing (2) and a second sealing means (23, 24) between the separating wall (20) and the cover (5), the first sealing means (21, 22) and the second sealing means (23, 24) being on each side of the junction plane (P).

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