Inductive position sensor integrated in motor housing

Abstract

The invention relates to an inductive position sensor (1) for a rotating electrical machine, comprising: a printed circuit board (10) on which is arranged at least one emitting element (11) intended to emit an oscillating magnetic field towards a rotating target in order to generate a modified magnetic field; and at least one receiving device (12) intended to detect said modified magnetic field, characterized in that said inductive position sensor is configured to form at least part of a housing (14) of the electric machine.

Description

Technical Field

[0001] This invention relates to the field of position sensors, and more specifically to a sensing position sensor integrated into a motor housing. Background Technology

[0002] A position sensor known as an eddy current sensor uses an oscillating magnetic field to determine the angular position of a rotating target that forms a coupling element.

[0003] These position sensors are particularly useful in electric or hybrid vehicle motors, which include a rotor that rotates relative to the stator.

[0004] Determine the angular position of the rotor relative to the stator.

[0005] The target is mounted at the end of the rotor shaft to modify the oscillating magnetic field emitted by the transmitter.

[0006] The target is centered relative to the rotor's axis of rotation.

[0007] The target comprises several blades that provide a magnetic field pattern relative to the rotor's axis of rotation.

[0008] The position sensor is fixedly mounted relative to the stator, facing the target and the end of the rotor.

[0009] The position sensor includes a printed circuit board, referred to as a PCB (Printed Circuit Board), which includes at least one emitting element designed to emit an oscillating magnetic field toward a target to generate a modified oscillating magnetic field at a given frequency.

[0010] The printed circuit includes at least one receiving device designed to detect the modified oscillating magnetic field and transmit it to a signal processing unit provided on the printed circuit to infer the angular position of the target.

[0011] The sensor is enclosed by a cover.

[0012] Typically, position sensors are positioned and held in place by screws on a metal motor housing.

[0013] The downside of this component is that it requires multiple screws, a plastic housing, and metal parts to be assembled together, which incurs additional costs.

[0014] Furthermore, the assembly of multiple components leads to inaccurate centering and reduces the performance of the position sensor. Summary of the Invention

[0015] Therefore, the present invention aims to overcome one of the shortcomings of the prior art by proposing a position sensor integrated in the motor housing.

[0016] To this end, the present invention proposes a position sensor for a rotating electric motor, comprising a printed circuit board having at least one transmitting element disposed thereon for transmitting an oscillating magnetic field to a rotating target to generate a modified magnetic field, and at least one receiving device for detecting the modified magnetic field, the sensor being configured to form at least a portion of the motor housing.

[0017] According to one embodiment of the present invention, the position sensor is integrated into the motor housing and forms a single piece with the housing.

[0018] In this way, assembly is optimized, assembly tolerances are reduced, and overall costs are lowered.

[0019] According to one embodiment of the present invention, the position sensor includes a recess for arranging a printed circuit board of the sensor.

[0020] According to one embodiment of the invention, the recess is closed by a cap, for example, made of plastic.

[0021] According to one embodiment of the invention, the sensor is configured to allow fluid to circulate up to the interior of the motor.

[0022] According to one embodiment of the invention, the sensor includes an opening that allows fluid to pass through.

[0023] According to one embodiment of the invention, the opening extends through a conduit configured to lead to the shaft of the motor.

[0024] According to one embodiment of the invention, the sensor includes a sealing gasket disposed on the lower surface of the housing along the contour of the housing.

[0025] According to one embodiment of the invention, the sensor includes a fluid inlet at the opening, which is formed by a metal or plastic component assembled on the upper surface of the housing.

[0026] The present invention also relates to a motor including a sensor according to the present invention. Attached Figure Description

[0027] Other objects, features, and advantages of the invention will be better understood and will become more apparent from the following description, with reference to the accompanying drawings, which are given by way of example, in which:

[0028] [ Figure 1 [Illustration of the electronic board of the sensor according to the present invention]

[0029] [ Figure 2 [This is a front view of the sensor according to the invention, viewed from below.]

[0030] [ Figure 3[This is a front view of the sensor according to the invention, with a closed plate, as viewed from below.]

[0031] [ Figure 4 [This is a top view of the sensor according to the invention.] Detailed Implementation

[0032] This invention relates to a position sensor 1, such as [ Figure 1 ]to[ Figure 4 As shown in the figure, it is integrated into the motor housing of the motor.

[0033] The position sensor 1 uses a magnetic field to determine the angular position of a rotating target (not shown) that serves as a coupling element.

[0034] The sensing position sensor 1 and the target are intended to be installed in a rotating electric motor, such as the motor of an electric or hybrid vehicle, which includes a rotor that rotates relative to the stator.

[0035] Determine the angular position of the rotor relative to the stator.

[0036] The target is mounted on the end of the rotor shaft to modify the magnetic field emitted by the transmitter.

[0037] According to one embodiment of the invention, the target includes a rotation axis aligned with the rotation axis of the rotor.

[0038] The target consists of multiple blades that provide a repeating and periodic magnetic field pattern relative to the rotor's axis of rotation.

[0039] According to one embodiment of the invention, sensor 1 is arranged to face the target and the rotor.

[0040] Therefore, in order to position on the shaft, there is a rotor / stator, then a target, and then a position sensor.

[0041] The target and sensor are arranged parallel to each other and perpendicular to the axis of the rotor shaft.

[0042] According to one embodiment of the present invention, sensor 1 is a through-type sensor, that is, the rotor shaft passes through the center of the sensor.

[0043] According to one embodiment of the present invention, sensor 1 is a non-through sensor, that is, it is arranged at the end of the rotor shaft.

[0044] The sensing position sensor 1 includes at least one printed circuit board 10, referred to as a PCB (Printed Circuit Board), which includes at least one emitting element 11 designed to emit an oscillating magnetic field toward a target, the target returning the modified oscillating magnetic field at a given frequency.

[0045] The printed circuit board 10 includes a receiving device 12 for detecting a modified oscillating magnetic field and sending it to a signal processing unit 13 to measure the angular position of a target.

[0046] The modified oscillating magnetic field generates an electromotive force of a given frequency in the receiving device 12. This electromotive force is processed by the signal processing unit 13 to provide an output signal capable of measuring the position of the target.

[0047] The position sensor 1 is fixedly installed relative to the stator.

[0048] The transmitting element 11 and the receiving device 12 of the sensing position sensor 1 are positioned to face the target.

[0049] According to one embodiment of the invention, the receiving device 12 includes a plurality of windings and has a circular cross-section, more precisely an annular cross-section.

[0050] According to one embodiment of the present invention, the number of windings of the receiving device 12 is proportional to the number of blades (or corner sectors) of the target.

[0051] According to one embodiment of the invention, the target includes at least two corner sectors 21, such as 3, 4, 5 or 6 corner sectors.

[0052] The printed circuit board 10, the transmitting element 11, and the receiving device 12 are housed in at least one recess 16 and supported by the base of the recess.

[0053] The recess forms the body 16 of the sensor 1.

[0054] According to one embodiment of the present invention, the signal processing unit 13 is positioned on the same substrate as the transmitting and receiving elements or on another substrate and is housed in the recess 16.

[0055] In the context of this invention, the sensor is configured to form at least a portion of the housing 14 of the motor.

[0056] In other words, sensor 1 is integrated into the motor housing 14.

[0057] The motor housing 14 and the sensor recess 16 are formed as a single piece.

[0058] In this way, assembly is optimized, assembly tolerances are reduced, and overall costs are lowered.

[0059] According to one embodiment of the invention, the housing 14 is made of a shielding material, such as plastic or steel with ferromagnetic particles.

[0060] This allows for the limitation of the propagation of fields emitted by sensors.

[0061] According to one embodiment of the invention, the housing 14 is made of plastic.

[0062] Therefore, the sensor has the shape of a standard motor housing 14, wherein a recess 16 is provided for arranging the printed circuit board 10 of the sensor 1. According to one embodiment of the invention, the recess 16 is arranged such that the transmitting element 11 and the receiving element 12 face the target.

[0063] According to one embodiment of the invention, the recess 16 is substantially located at the center of the housing 14, and for example, at the center of the housing 14.

[0064] According to one embodiment of the invention, the recess 16 includes an opening located on the lower or upper surface of the housing 14. The lower surface is a surface oriented toward the motor.

[0065] The outer surface is defined relative to the lower surface oriented toward the motor.

[0066] According to one embodiment of the invention, the recess 16 forms a protrusion 167 on the surface of the housing 14 opposite to the surface of its opening.

[0067] According to one embodiment of the invention, the recess 16 is closed by a cover 17. According to one embodiment of the invention, the cover 17 is made of plastic.

[0068] According to one embodiment of the invention, housing 14 includes a seal 161 arranged on the contour of housing to enable a sealed motor compartment.

[0069] A seal 161 is disposed on the lower surface of the housing 14. According to one embodiment of the invention, the seal 161 is made of a flexible plastic material of the elastomer type.

[0070] According to one embodiment of the invention, the housing 14 includes a connection system 162 on its outer surface, which allows the printed circuit 10 to be connected to the outside.

[0071] According to one embodiment of the invention, the housing 14 includes an opening 163 that allows fluid to pass through.

[0072] According to one embodiment of the present invention, the fluid is lubricating oil for an electric motor.

[0073] According to one embodiment of the invention, the opening 163 extends from the conduit 164. According to another embodiment of the invention, the conduit 164 passes through the recess 16 and the printed circuit board 10.

[0074] Therefore, the conduit 164 is arranged on the same surface as the recess 16.

[0075] According to one embodiment of the invention, the conduit 164 is configured to extend into the rotor shaft.

[0076] Therefore, the rotor shaft includes an opening that allows circulating fluid to be distributed throughout the motor due to centrifugal force, which pushes the fluid against the shaft wall.

[0077] According to one embodiment of the invention, the conduit 164 is an extension or additional component of the housing 14, for example, overmolded with the housing.

[0078] According to one embodiment of the invention, the conduit 164 is arranged along the longitudinal axis of the rotor.

[0079] According to one embodiment of the invention, the fluid inlet at the opening 163 is formed by a component 166 made of metal or plastic, such as a hose, assembled onto the housing.

[0080] The component 166 is arranged on the surface of the housing opposite to the surface where the recess is located.

[0081] This component allows fluid to reach the motor shaft, where it will circulate in a fluid conduit.

[0082] According to one embodiment of the invention, the housing 14 includes at least two openings 165 on its periphery to allow it to be attached to the housing of the motor.

[0083] Opening 165 allows for attachment, for example, by screwing a screw through the opening.

[0084] Therefore, sensor 1 is configured to allow fluid to circulate up to the inside of the rotor shaft.

[0085] The passage of the conduit 164 at the center of the sensor 1 allows for fully cylindrical antennas 11 and 12, which enables the maintenance of good signal accuracy.

[0086] The present invention also relates to a motor including the sensor 1 as described above.

[0087] The scope of this invention is not limited to the details given above, and many other specific embodiments are permissible without departing from the scope of the invention. Therefore, this embodiment must be considered by way of illustration and modifications can be made without departing from the scope defined by the claims.

Claims

1. An inductive position sensor (1) for a rotary electric machine, comprising a printed circuit board (10) on which at least one transmitting element (11) and at least one receiving device (12) are arranged, said at least one transmitting element (11) being intended to emit an oscillating magnetic field towards a rotary target to generate a modified magnetic field, said at least one receiving device (12) being intended to detect said modified magnetic field, characterized in that, The sensing position sensor (1) is configured to form at least a portion of the housing (14) of the motor.

2. The position sensor (1) according to claim 1 is integrated into the housing (14) of the motor.

3. The position sensor (1) according to claim 1 or 2, comprising a recess (16) on the printed circuit board (10) on which the sensor is disposed.

4. The inductive position sensor (1) according to any one of claims 1 to 3, wherein The recess (16) is closed by a cover (17), which is made of, for example, plastic.

5. The sensing position sensor (1) according to any one of claims 1 to 4 is configured to allow fluid circulation up to the interior of the motor.

6. The sensing position sensor (1) according to any one of claims 1 to 5, comprising an opening (163) allowing fluid to pass through.

7. The position sensor (1) according to claim 6, wherein, The opening (163) extends through a conduit (164) configured to lead to the shaft of the motor.

8. The position sensor (1) according to any one of claims 1 to 7, comprising a sealing gasket (161) disposed on the contour of the housing (14), the sealing gasket being disposed on the lower surface of the housing (14).

9. The sensing position sensor (1) according to any one of claims 1 to 8, comprising a fluid inlet (166) at the opening (163), the fluid inlet (166) being formed of a metal or plastic component assembled on the upper surface of the housing (14).

10. An electric motor comprising a sensor (1) according to any one of claims 1 to 9.

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