CN111954979A

CN111954979A - Lighting correction device with DC motor for vehicle

Info

Publication number: CN111954979A
Application number: CN201980020988.9A
Authority: CN
Inventors: 瓦西姆·布泽尔达; 安德森·诺罗尼亚
Original assignee: Emerin Systems
Current assignee: Emerin Systems
Priority date: 2018-03-22
Filing date: 2019-01-29
Publication date: 2020-11-17
Anticipated expiration: 2039-01-29
Also published as: WO2019180330A1; FR3079177A1; CN111954979B; FR3079177B1

Abstract

The invention relates to a lighting correction device for a motor vehicle having a direct current motor. The device (1) comprises a corrector (3) for a motor vehicle headlight (2), which corrector (3) has a direct current motor (6) which can be controlled to move a mechanical element (5) therein. In order to correct the illumination, the corrector (3) further comprises: an auxiliary unit (20) comprising counting means (21) for detecting, when controlled, the pulses generated on the collector of the electric motor (6) by brush commutation and counting in real time the number of pulses thus detected; a processing unit (22) for determining in real time the current rotation value of the motor (6) and the current position of the corrector (3) according to said counted number of pulses; the transmitting unit (23) is capable of transmitting the current position thus determined in real time.

Description

Lighting correction device with DC motor for vehicle

[ technical field ] A method for producing a semiconductor device

The invention relates to a lighting correction device having a direct current motor, a method for lighting correction and a control system for a lighting assembly of a motor vehicle, comprising such a lighting correction device.

[ background of the invention ]

Generally, a lighting assembly for a motor vehicle comprises at least one headlight. Headlamps generally comprise a light source arranged in front of an optical reflector, the whole light source generating a light beam designed to be projected outside the motor vehicle, whether in front or behind.

Generally, the light beam produced by such a headlamp should be able to be adjusted, in particular in order to adapt its range. For this purpose, the headlight comprises a corrector suitable for this adjustment.

As an illustration, a headlight for motor vehicle lighting is known from the document FR-2918938 of the applicant, which is provided with a lighting unit that emits a light beam directed to the road located in front of the vehicle. In order to direct the light beam and thus adjust the height of said light beam, the position of the reflector inside the lighting unit is changed by means of a lighting corrector comprising an electrical module. The electrical module is provided with an electric motor and an electronic card. The rotation of the motor causes a translational movement of a mechanical element, for example an adjustment lever, which is adapted to tilt the optical reflector. The electric motor is controlled according to a regulating sequence, usually located on the dashboard, which is generated by the control (or regulating) elements within the reach of the vehicle driver.

The electronic card of the corrector has a dual function:

-operating the motor on command (rotation in one direction or the other); and

-determining the position of a mechanical element displaced by the electric motor to realize the servomechanism.

However, such electric motor electronic cards are rather expensive, in particular compared to the total cost of the corrector.

[ summary of the invention ]

The object of the invention is to provide an illumination correction device with reduced costs, comprising at least one corrector designed for a headlight of a motor vehicle and provided with an electric motor.

According to the invention, the corrector has a direct current motor comprising at least a stator, a rotor, a collector and a brush, the motor being controllable by means of received control signals so as to generate a rotation capable of moving a mechanical element along a given path, comprising an auxiliary unit having the following functions:

-counting means for detecting in real time the pulses generated by brush commutation on the collector when the motor is rotating and for counting in real time the number of detected pulses, said number of pulses being proportional to the value of rotation of said direct current motor;

-a processing unit for determining in real time a current rotation value of the motor from said counted number of pulses and determining a current position of the corrector from said current rotation value and at least one given reference position with respect to at least one end stop of the motor; and

-a transmitting unit capable of transmitting the determined current position in real time.

Preferably, the processing unit is adapted to determine in real time the current position of a specific point (e.g. a connection point) of the mechanical element displaced by the motor as the current position of the corrector.

Thus, thanks to the invention, the current position can be determined by simply implementing the pulse counting without any expensive and bulky means. As described below, this information can be used to avoid conventional servo control implemented by conventional electronic cards and reduce the overall cost involved with electronic cards in the case of multiple headlights.

In the context of the present invention, each pulse is caused by the commutation of a brush on a collector during rotation of the motor. If the number of commutations P per revolution (commutation) of the motor during rotation is known, the rotation value VR rotation corresponding to the size of the motor, i.e. the number of revolutions performed starting from the counted number of pulses N, can be calculated, due to the characteristics and arrangement of the collectors and brushes. More precisely, there is a relationship VR ═ N/P.

Furthermore, knowing the structure of the corrector associated to the mechanical element and therefore the displacement distance of the mechanical element for each revolution of the motor, it is possible to deduce from the rotation value VR the current position of the mechanical element. Thus, the corrected illumination angle is rotated.

Advantageously, the pulses thus counted are current peaks or voltage peaks.

Furthermore, in a particular embodiment, the motor comprises two end stops, each representing a reference position in one direction or the other, respectively.

As mentioned above, the invention also relates to a method for lighting correction by means of a lighting correction device, said method comprising a control step comprising the control of an electric motor comprising a stator, a rotor, a collector and a brush, by means of which control signals are generated to generate a rotation capable of moving a mechanical element to correct the lighting.

According to the invention, the illumination correction method comprises a series of steps comprising:

-a counting step, carried out by counting means, comprising, in real time, detecting, in the control step and in the counting process, the pulses generated by the commutation of the brushes on the collector during the rotation of the motor, and counting in real time the number of pulses thus detected, said number of pulses being proportional to the rotation value of said direct current motor;

-a processing step, performed by a processing unit, comprising the determination of a current rotation value of the motor in real time as a function of said counted number of pulses, and the determination of a current position of the corrector as a function of said current rotation value and at least one given reference position with respect to at least one end stop of the motor; and

-a transmitting step, implemented by the transmitting unit, comprising transmitting in real time the current position thus determined.

Advantageously, the processing step involves determining in real time a specific point of the mechanical element moved by the motor as the current position of the corrector.

The invention also relates to a control system for a lighting assembly. The control system comprises at least one lighting correction device as described above, and a control unit offset with respect to the corrector and to the auxiliary unit to which the corrector is connected, said control unit being adapted to receive the current position determined and sent by the auxiliary unit and to determine a control signal for the motor of the corrector, said control signal being transmitted to the motor by an electrical connection. Advantageously, the control unit is configured to determine the control signal of the motor of the corrector from said current position thus received.

Thus, it is no longer necessary to provide a conventional electronic card at the electric motor.

In a preferred embodiment, the control system comprises at least two lighting correction devices, each of said lighting correction devices being connected to the control unit, and the control unit is configured to receive the current position determined by the auxiliary unit in each of said lighting correction devices and to determine a control signal for the motor of the corrector of each of said lighting correction devices.

In this preferred embodiment, a single control unit (necessary and sufficient) to control multiple motors, reduces costs compared to conventional architectures in which each motor is controlled by its own electronic card.

Furthermore, the invention relates to a lighting assembly for a motor vehicle, comprising at least one headlamp comprising at least one light source configured to generate a light beam and mechanical elements capable of moving the light beam.

According to the invention, the lighting assembly further comprises a control system as described above.

In a particular embodiment, the lighting assembly comprises at least two headlights, each headlight comprising a corrector and a single control unit for the two headlights.

[ description of the drawings ]

The invention will be better understood and other objects, details, characteristics and advantages will appear more clearly in the course of the following detailed description of embodiments of the invention, which is given by way of illustrative and non-limiting example only, with reference to the accompanying schematic drawings. In these drawings:

figure 1 is a schematic view of a particular embodiment of the illumination correction device according to the invention.

Fig. 2 schematically shows a dc brush-commutated electric motor as part of a lamp correction device.

Figures 3A and 3B schematically show different positions between the brush and the collector of the electric motor; and

figure 4 is a schematic view of a particular embodiment of a lighting assembly according to the invention.

[ detailed description ] embodiments

The illumination correction device 1 (hereinafter "device 1") schematically illustrated in the particular embodiment of fig. 1 is intended to correct at least one light beam F) of a headlight 2 (as part of a car lighting assembly). The device 1 comprises a corrector 3.

As shown in fig. 1, the headlight 2 comprises in a typical manner a light source 4, which light source 4 is arranged, for example, in front of an optical reflector (not shown) and is capable of generating a light beam F which is projected outside the motor vehicle, forwards or backwards. The headlight 2 comprises mechanical elements (representing displacement means) 5 capable of moving said light beam F.

The direction of the light beam F must be adjustable, in particular its height and its extent. For this purpose, the headlight 2 is equipped with a corrector 3, which corrector 3 acts on the mechanical element 5, as indicated by the arrow E shown in dashed lines in fig. 1.

As schematically shown in fig. 1, the corrector 3 is provided with a motor 6. The electric motor 6 can be controlled by means of control signals received by the electric connection 7 so as to generate a rotation capable of moving the mechanical element 5 along a given path. This displacement movement is intended to move the light beam generated by the headlight 2 in a typical manner (so as to correct or vary the illumination angle α, with respect to the reference direction DR), the motor 6 acting on the mechanical element 5 by the action of the mechanical element 5. As shown, the mechanical element 5 is a typical control rod that allows to adjust the position of the optical mirror by its stroke (translation) (generated by the rotation of the motor, through a gear train (not shown)) so as to vary the illumination angle of the light beam F.

In the context of the present invention, the motor 6 is a brushed Direct Current (Direct Current) motor.

As shown in fig. 2, the motor 6 typically includes:

a stator 8 (inductor) with

magnets

9 and 10 to generate a magnetic field;

a rotor 11 (armature) with windings 12 and a shaft 13, and a current collector 14 with segments (or metal pads) 14A, 14B and 14C; and

brushes 15 and 16 connected to a source of electrical energy (not shown) by

electrical connections

17 and 18, respectively, and mounted to rub against collector 14 when rotor 13 rotates.

The electric motor 6 thus converts the electric energy (in the form of direct current) received through the

electric connectors

17 and 18 into mechanical energy, which is transmitted through the rotation of the hub 13, as indicated by the arrow F (representing one of the two possible directions of rotation of the electric motor 6). This rotation of the shaft 13 can be converted into a translation (stroke) of the mechanical element 5 by means of a gear train (not shown). The motor 6 can be controlled to rotate in one or the other of the two directions, thus producing a translation of the mechanical element 5 in one or the other of the two directions, and thus an adjustment of the illumination direction in one or the other of the two directions, and this according to the desired amplitude.

According to the invention, said corrector 3 of the device 1 comprises an auxiliary unit 20. The auxiliary unit 20 comprises a counting device 21, as schematically shown in fig. 1, which is adapted to detect in real time, as schematically indicated by the arrow H in broken lines, the pulses generated by the commutation of its

brushes

15 and 16 on the collector 14 being controlled as the motor 6 rotates. The counting device 21 is also adapted to count the number of pulses thus detected in real time.

During normal operation of the motor 6, commutation of the

brushes

15 and 16 on the collector 14 (provided by the

segments

14A, 14B and 14C) causes a variation in the total resistance Rm of the motor, from 2/3.R (in the example of fig. 3A) to 1/2.R (in the example of fig. 3A), R representing the resistance of the winding. This instantaneous change in resistance produces peaks in current and voltage during each commutation, these peaks representing the pulses. The counting means 21 comprise typical means (in particular electrical means) suitable for counting the number of peaks of current or of voltage generated during the rotation of the electric motor 6. The number of pulses (or peaks) corresponds to a rotation value VR of the motor defined as follows.

As schematically shown in fig. 1, the auxiliary unit 20 also comprises:

a processing (or value determining) unit 22 adapted to determine in real time a current rotation value VR of the motor 6 from said counted N pulses and to determine in real time from said current rotation value VR that the current position of the corrector 3 has at least one given reference position with respect to at least one end stop of the motor 6. The processing unit 22 is designed to determine in real time the current position of a particular point, the current position of which (for example, one end or a connection point) of the mechanical element 5 is displaced under control of the electric motor 6, as the current position of the corrector 3; and

a transmitting unit 23 capable of transmitting the thus determined current rotation value VR and/or current position to a user system as defined below in real time via a connection 24.

This information can be used to avoid having to implement conventional servo control implemented by conventional electronic cards.

In the context of the present invention, each pulse is caused by the commutation of the

brushes

15 and 16 on the collector 14 during the rotation of the motor 6. The number of commutations P per revolution (rotation) during rotation of the motor 3 is known from the characteristics (the number of

segments

14A, 14B, 14C, etc.) and the layout of the current collector 14 and the

brushes

15 and 16. Therefore, the rotation value VR corresponding to the rotation amount, that is, the number of turns during the control can be calculated. With the processed VR ═ N/P, the VR value is calculated by the processing unit 22 with the number of counted pulses N.

Furthermore, knowing the mechanical structure of corrector 3 in relation to mechanical element 5, and therefore the displacement distance of mechanical element 5 per revolution of motor 6, it is possible to deduce, rotation value VR, the current position of mechanical element 5 and therefore the corrected illumination angle.

Furthermore, in a particular embodiment, the electric motor 6 comprises two end stops (not shown), for example radial end stops, so that it is possible to stop the rotation of the electric motor 6 (and therefore of the shaft 13) in one direction and in the other direction, respectively, when these end points are reached. The stops produced by the end stops show the reference position in one direction or the other, respectively.

These end stops make it possible in particular to carry out an initialization (seeking a reference position) of the device 1 during each use of the device or only at the first start-up and after a power-off during its functioning.

In a preferred embodiment, the (illumination correction) device 1 is part of a control system 25 for an illumination assembly 30, as shown in fig. 4.

The control system 25 comprises at least one device 1 as described above with reference to fig. 1 and a control unit 26 (fig. 1) offset with respect to the corrector 3 and the auxiliary unit 20 of the corrector 3 connected to the device 1.

The control unit 26 is designed to receive the current position determined and transmitted by the auxiliary unit 20 of the device 1 via the connection 24. The control unit 26 comprises a data processing unit 27 to determine control signals for the motor 6 of the corrector 3. The control signals determined by the data processing unit 27 are transmitted to the electric motor 6 via the electrical connection 7.

The data processing unit 27 of the control unit 26 is adapted to determine control signals for the motor 6 of the corrector 3 (via the connection 24) from said current position received.

The data processing unit 27 determines control signals in order to comply with a regulation sequence generated by an operator, in particular a driver of the vehicle, via a regulating unit 28, which is connected to the control unit 26 by a connection communicator 29. The adjustment unit 28 is preferably located within reach of the vehicle driver, typically on the dashboard. By way of illustration, and not limitation, the adjustment unit 28 may comprise a manual actuation element, such as a knob or joystick, such as a display screen, in particular a touch screen, and/or a voice control.

The data processing element 27 of the control unit 26 generates control signals designed to control the electric motor 6 according to the adjustment sequence thus received and generally also depending on other data, for example data relating to the position of the motor vehicle. These data are supplied by an array 31 of information sources via a connection 32 to the control unit 26. Illustratively, the array 31 may include, for example, a position sensor and/or a position calculation unit.

Furthermore, in the preferred embodiment shown in fig. 4, the lighting assembly 30 comprises a plurality of headlights 2. In the preferred embodiment, there is a single control unit 26, and it is associated with (and intended to control) a plurality of N headlights 2, labelled 2.1, 2.2, 2.N is an integer greater than or equal to 2.

Each of the headlights 2.1, 2.2, 2.N exhibits the characteristics and comprises the elements described above in relation to the headlight 2 of fig. 1.

Thus, in the preferred embodiment, the control system 25 comprises a plurality of N correctors 3, one for each different headlight 2, i.e. one corrector 3 for each headlight 2. The correctors 3, in particular their motors 6, are controlled by one and the same control unit 26. The preferred embodiment therefore comprises a single control unit 26 for a plurality of correctors 3, which can reduce costs compared to conventional architectures in which each corrector is equipped with its own electronic card for control.

In the preferred embodiment, the control system 25 includes a plurality of devices 1 (for illumination correction). Each of said devices 1 is connected to a control unit 26, and the control unit 26 is adapted to receive the current position determined by the auxiliary unit of each of said lighting correction devices and to determine a control signal for the motor of the corrector of each lighting correction device.

Thus, in the preferred embodiment, a single control unit 26 is sufficient to control a plurality of electric motors 6, enabling a reduction in cost and size compared to conventional architectures where a single motor would be controlled by its own electronic card.

In an alternative embodiment (not shown), the processing unit 22 for calculating the value VR and the current position is not arranged directly in the corrector 3 in a position close to the motor 6 (as shown in fig. 1), but is offset and mounted, for example, in the control unit 26. In this case, the auxiliary unit 20 in the vicinity of the motor 6 merely determines the number of pulses and transmits this information to the control unit 26 in order to deduce therefrom the current position.

The preferred embodiment described above with respect to fig. 4 has inter alia the following advantages:

-each conventional electronic card corresponding to each specific corrector 3 is cancelled;

centralized control of the corrector 3 in a single (electronic) control unit 26;

-reduction of costs; and

a more compact mechanical design.

Claims

1. An illumination correction device, the illumination correction device (1) comprising at least one corrector (3) for a motor vehicle headlight (2), the corrector (3) having a direct current motor (6), the motor (6) comprising at least one stator (10), a rotor (11), a current collector (14) and brushes (15, 16), the motor (6) being controlled by means of received control signals to generate a rotation of a moving mechanical element (5) to correct the illumination,

characterized in that said corrector (3) comprises an auxiliary unit (20) comprising:

-counting means (21) for detecting in real time the pulses generated by the commutation of the brushes (15, 16) on the collector (14) when the motor (6) is rotating, and for counting in real time the number of detected pulses, said number of pulses being proportional to the rotation value of said direct current motor (6);

-a processing unit (22) for determining in real time a current rotation value of the motor (6) from said counted number of pulses and determining a current position of the corrector (3) from said current rotation value and at least one given reference position with respect to at least one end stop of the motor (6); and

-a transmitting unit (23) for transmitting the determined current position in real time.

2. The apparatus of claim 1, wherein the first and second electrodes are disposed on opposite sides of the housing,

wherein the pulse is a current peak or a voltage peak.

3. The apparatus according to any one of claims 1 and 2,

characterized in that the motor (6) comprises two end stops, each representing a reference position in one direction or the other, respectively.

4. The device according to any one of the preceding claims,

characterized in that the processing unit (22) is adapted to determine in real time the current position of a specific point of the mechanical element (5) moved by the motor (6) as the current position of the corrector (3).

5. Method for lighting correction by means of a lighting correction device (1), said lighting correction device (1) comprising at least one corrector (3) intended for motor vehicle headlights (2), said corrector (3) having a direct current motor (6), said method comprising a control step comprising the control of the motor (6) comprising a stator (10), a rotor (11), a collector (14) and brushes (15, 16), by means of control signals to generate a rotation of a moving mechanical element (5) to correct the lighting,

it is characterized in that it involves a series of steps comprising:

-a counting step, carried out by counting means (21), comprising detecting in real time, when controlled in the control step and in the counting process, the pulses generated by the commutation of the brushes (15, 16) on the collector (14) during the rotation of the motor (6), and counting in real time the number of detected pulses, said number of pulses being proportional to the rotation value of said direct current motor (6);

-a processing step, performed by a processing unit (22), comprising determining in real time a current rotation value of the motor (6) as a function of said counted number of pulses and determining a current position of the corrector (3) from said current rotation value and at least one given reference position with respect to at least one end stop of the motor (6); and

-a transmitting step, carried out by the transmitting unit (23), comprising transmitting the determined current position in real time.

6. The method of claim 5, wherein the first and second light sources are selected from the group consisting of,

characterized in that said processing step involves determining in real time a specific point of the mechanical element (5) moved by the motor (6) as the current position of the corrector (3).

7. A control system for a lighting assembly is provided,

characterized in that it comprises at least one lighting correction device (1) according to any one of claims 1 to 4 and a control unit (26) biased with respect to the corrector (3) and with respect to the connected auxiliary unit (20), said control unit (26) being adapted to receive the current position determined and sent by the auxiliary unit (20) and to determine a control signal of the electric motor (6) of the corrector (3) to be transmitted to the electric motor (6) through the electric connection (7).

8. The control system as set forth in claim 7,

characterized in that the control unit (26) is configured to determine a control signal of the electric motor (6) of the corrector (3) from the received current position.

9. Control system according to one of claims 7 and 8, characterized in that it comprises at least two lighting correction devices (1), each of said lighting correction devices (1) being connected to a control unit (26), and in that the control unit (26) is configured to receive the current position determined by the auxiliary unit (20) of each of said lighting correction devices (1) and to determine a control signal for the motor (6) of the corrector (3) of each of said lighting correction devices (1).

10. A lighting assembly for a motor vehicle, the lighting assembly (30) comprising at least one headlamp (2), the headlamp (1) comprising at least one light source (4) configured to generate a light beam (F) and a mechanical element (5) to move the light beam (F),

characterized in that it further comprises a control system (25) according to any one of claims 7 to 9.

11. The lighting assembly as set forth in claim 9,

characterized in that it comprises at least two headlights (2), each headlight comprising a corrector (3) and a single control unit (26) for both headlights (2).