Headlight module optimized for cycling

Abstract

The invention relates to a lighting module (1) for a headlamp, comprising: - a light source (4); - an electrical power supply circuit (6) with: a power supply interface (62) for the light source, a connection interface (61) for a battery, an accelerometer (65), a control circuit (63) for applying different power levels to the power supply interface (62), a processing circuit (64) connected to the accelerometer (65), the processing circuit (64) being configured to determine the transverse amplitude and the vertical amplitude of an acceleration and to: - a) determine a first electrical power level setpoint as a function of the determined vertical acceleration amplitude; b) if the determined transverse acceleration amplitude is greater than a first threshold, apply to the control circuit (63) a second electrical power level setpoint greater than the first setpoint;c) repeat steps a) and b) after a predetermined time. Figure to be published with the abbreviation: Fig. 1;

Description

Title of the invention: Lighting module for headlamp optimized for cycling

[0001] The invention relates to headlamps, and in particular to the methods of powering headlamps. Headlamps have been developed because they allow the light generated to follow the head movements and the gaze of the user and are therefore particularly suitable for sports.

[0002] Sports practice and in particular endurance or ultra-distance activities lead users to exercise more at night. To be able to provide optimal lighting over a long period, headlamps must then have high-capacity batteries. Such capacity comes at the expense of weight, which the user seeks to minimize, in particular for competitive practice or for long hours. An alternative is to reduce the power consumption of the lamp by reducing the brightness of the lamp. The lighting may then prove insufficient on uneven terrain or at high speed.

[0003] Lamps with variable power depending on the conditions of use are known. However, such lamps may prove incompatible with cycling, as changes of direction on a bike occur at a greater speed than in running, which may require increased vigilance on the part of the user. Similarly, variations between uneven areas and less uneven areas may occur more quickly, due to the speed of the bike. Furthermore, there is no variable power lamp that is optimized both for cycling and for other disciplines such as running. Such a need is growing to the extent that users may want the same lamp for different activities, in particular for combined sports such as triathlon, adventure raids or Ironman.

[0004] The invention aims to solve one or more of these drawbacks. The invention thus relates to a lighting module for a headlamp, comprising: -a light source; -a circuit for supplying electricity to the light source, including: a power supply interface for the light source, an interface for connecting an electric battery, an accelerometer, a control circuit configured to apply different levels of electric power to the power supply interface, a processing circuit connected to the accelerometer, the processing circuit being configured to determine the transverse amplitude and the vertical amplitude of an acceleration of the lighting module measured by the accelerometer and configured to, in a first mode of functioning : -a) determine a first electrical power level setpoint as a function of the amplitude of the determined vertical acceleration; b)-if the amplitude of the determined transverse acceleration is greater than a first threshold, apply to the control circuit (63) a second electrical power level setpoint greater than the first setpoint; c) repeat steps a) and b) after a predetermined time.

[0005] The invention also relates to the following variants. Those skilled in the art will understand that each of the features of the following variants can be independently combined with the above features, without constituting an intermediate generalization.

[0006] According to a variant, the first electrical power level setpoint is determined by the processing module on a scale of at least 5 increasing power levels, the second power level setpoint being determined by increasing the first power level setpoint by 2 power levels.

[0007] According to another variant, said first threshold is between 0.15 and 0.4 g.

[0008] According to another variant, said predetermined duration is at least equal to 3 seconds.

[0009] According to yet another variant, the processing circuit is configured to determine the longitudinal amplitude of the acceleration of the lighting module measured by the accelerometer and configured to determine the speed of the lighting module by integrating the measured longitudinal amplitude, the processing circuit being configured to determine the first power level setpoint also as a function of the measured longitudinal amplitude.

[0010] According to a variant, the processing module being configured to, in a second operating mode: -d) apply a third electrical power level setpoint based on the amplitude of the determined vertical acceleration; -e) repeat step d) after a predetermined time; -the module further comprising a switch for selectively switching between the first and second operating modes.

[0011] The invention also relates to a headlamp comprising a lighting module as described above.

[0012] According to one variant, the headlamp comprises a front strap secured to the lighting module or a velvet-hook type fixing element.

[0013] Other characteristics and advantages of the invention will emerge clearly from the description given below, for information purposes only and in no way limiting, with reference to the appended drawings, in which:

[0014] [Fig-1] is an exploded perspective view of a headlamp lighting module according to an exemplary embodiment;

[0015] [Fig.2] is a schematic representation of an example of a power supply circuit of the lighting module;

[0016] [Fig.3] is a front view of the lighting module of [Fig.l];

[0017] [Fig.4] is an enlarged front view of the lighting module of [Fig.l] at the level of a switch;

[0018] [Fig.5] is a schematic diagram of managing examples of variations in electrical power.

[0019] [Fig.l] is an exploded perspective view of a lighting module 1 for a headlamp. [Fig.3] is a front view of this lighting module 1. [Fig.4] is an enlarged front view of a detail of this lighting module 1. The lighting module 1 comprises a light source 4 and a power supply circuit 6 (not shown in [Fig.l]). The lighting module 1 here also comprises a housing 2, caps 31, 32, and a control button or switch 5.

[0020] The longitudinal, transverse and vertical directions are defined in relation to the normal use of a headlamp, namely for example:

[0021] -the longitudinal direction corresponds both to the direction of advance of the user and to a normal to the light source or to the main director of the light beam;

[0022] -the transverse direction corresponds to a horizontal direction perpendicular to the longitudinal direction, the transverse direction here corresponds to a direction connecting the caps 31 and 32;

[0023] -the vertical direction corresponds to a vertical direction perpendicular to the vertical direction and corresponds for example to an axis passing through the head and a foot of the user.

[0024] The housing 2 here comprises housings 21 and 22 for one or more batteries. The housings 21 and 22 are here tubular in shape and oriented in the transverse direction X of the lighting module 1. The housings 21 and 22 communicate here and allow a battery to be inserted over the majority of the length of the housing 2. The module 1 here further comprises the caps 31 and 32 intended to ensure the closure of the housings 21 and 22 respectively. The caps 31 and 32 here comprise internal threads cooperating with threads provided on the outside of the housing 2. The caps 31 and 32 advantageously cooperate with the housing 2 to seal the housings 21 and 22 in a sealed manner.

[0025] The housings 21 and 22 are for example designed to receive one or more Lithium-ion batteries in the standard 18650 format. Contacts are arranged in a manner known per se in the housings 21 and 22 and at the level of the caps 31 and 32, in order to apply the potential of the batteries to a connection interface 61 of the power supply circuit 6 (illustrated schematically in [Fig.2]).

[0026] The switch 5 is here provided at the level of the cap 32. The switch 5 advantageously makes it possible to turn on / off the light source 4 or to change the operating mode as detailed below. The switch 5 is here pivoting and is interfaced with the electrical supply circuit 6.

[0027] The housing 2 here comprises a protrusion 23. The protrusion 23 is arranged to project in the longitudinal direction Z relative to the housings 21 and 22. The protrusion 23 makes it possible to house the electrical power supply circuit 6. The light source 4 is here fixed in the front end of the protrusion 23.

[0028] The housing 2 may include hoops (not shown) for securing it to a front strap, in a manner known per se for forming the headlamp.

[0029] [Fig. 2] is a schematic representation of the power supply circuit 6 according to one embodiment of the invention. The power supply circuit 6 comprises a power supply interface 62 of the light source, the connection interface 61, an accelerometer 65, a control circuit 63 and a processing circuit 64.

[0030] The connection interface 61 is intended to be connected to the terminals of an electric battery not shown. The control circuit 63 is configured to apply different levels of electric power to the power supply interface 62, to allow the lighting to be modulated by the light source 4. The processing circuit 64 is connected to the accelerometer 65. The processing circuit 64 is configured to determine the amplitude of an acceleration of the lighting module 1. The processing circuit 64 is also configured to provide an electric power level setpoint to the control circuit 63 as a function of the determined acceleration.

[0031] The processing circuit 64 is more particularly configured to determine the transverse amplitude and the vertical amplitude of an acceleration of the lighting module 1 measured by the accelerometer 65 and configured for, in a first operating mode (typically a bicycle mode): -a) determine a first electrical power level setpoint based on the amplitude of the determined vertical acceleration; b)-if the amplitude of the determined vertical acceleration is greater than a first threshold, apply to the control circuit (63) a second electrical power level setpoint greater than the first setpoint; c) repeat steps a) and b) after a predetermined time. With such a configuration, the vertical acceleration is first taken into account to check whether the terrain is uneven, then the transverse acceleration is taken into account to determine whether the user is in a significant bend. The electrical power level is thus increased if a significant bend is identified. The user will have thus better visibility in an area requiring more attention. Since accelerations when cornering on a bike are in practice less significant than when running for the same vertical acceleration, such operation allows for precise detection of the presence of a corner. The power level corresponding to the second instruction can be maintained for the predetermined duration, for example 3 seconds.

[0032] In order to quickly take into account the appearance of an accident zone, the determination of the first power level setpoint as a function of the vertical acceleration can advantageously be carried out at intermediate times during the predetermined duration. If the level determined for the first power level setpoint decreases or remains unchanged at an intermediate time, the applied electrical power level nevertheless remains unchanged during the predetermined duration. If, on the other hand, the level determined for the first power level setpoint increases due to an increase in the vertical acceleration, the second power level setpoint increases and the applied electrical power level increases.

[0033] Two different time scales are then available: the predetermined duration guaranteeing the maintenance of a significant electrical power before reducing this power and improving autonomy, a shorter duration to update the power level to a higher level (rapid management of the appearance of uneven or turning terrain). By maintaining a higher light intensity for a certain time upon leaving an uneven area, the user will thus be able to immediately have this light intensity without having to wait for the detection of a new high vertical acceleration.

[0034] The processing circuit 64 advantageously has a certain number of different power levels, for example with a scale of at least 5 increasing power levels. During step a), the first setpoint is determined in one of these power levels as a function of the determined vertical acceleration. Advantageously, the second power level setpoint is determined by increasing by at least 2 power levels relative to the first determined power level setpoint.

[0035] The trigger threshold for the transition from the first setpoint to the second power level setpoint may, for example, be between 0.15 and 0.4g.

[0036] An example of implementation is illustrated by the diagram in [Fig.5]. The vertical acceleration is illustrated on the ordinate and the transverse acceleration on the abscissa.

[0037] The threshold SU corresponds to a transverse acceleration threshold. The thresholds S21, S22, S23, S24 correspond to vertical acceleration thresholds. The threshold S21 defines the limit between first and second electrical power levels, the threshold S22 defines the limit between second and third electrical power levels, the threshold S23 defines the boundary between third and fourth electrical power levels, and threshold S24 defines the boundary between fourth and fifth electrical power levels. The first to fifth electrical power levels are increasing electrical power levels on a scale.

[0038] First, a first electrical power level setpoint is determined as a function of the determined vertical acceleration. In the example, the vertical acceleration is between thresholds S21 and S22 and thus determines a first setpoint having the second power level. It is then determined that the determined transverse acceleration is greater than threshold S1 1. Starting from the first setpoint, the power level is increased by two levels, so that the second setpoint reaches the fourth power level.

[0039] During a following cycle, if the vertical acceleration leads to determining a lower first setpoint level, the second setpoint level is also lowered. Similarly, if during this following cycle, the transverse acceleration has decreased, the second setpoint level can be lowered. Monitoring the transverse and vertical accelerations after a predetermined duration thus makes it possible to reduce the electrical consumption when the terrain is less uneven or less winding. Since the change in power supply is induced automatically by the measurements of the accelerometer 65, the user does not need to act on his headlamp to benefit from an optimal operating mode when cycling.

[0040] The processing circuit 64 may also be configured to calculate a movement speed from the measurements of the accelerometer 65, for example by integration. The calculated speed may then be compared to a respective threshold for changing the electrical power level setpoint on the control circuit 63. The speed may in particular be taken into account in step a) to determine the first power level setpoint.

[0041]

[0042] To avoid taking into account the cyclical nature of certain accelerations linked to cycling, the processing circuit 64 is advantageously configured to determine the average of the instantaneous vertical acceleration and the average of the instantaneous transverse acceleration over a period of 1 second.

[0043] The processing circuit 64 may include a microprocessor implementing instructions of suitable software.

[0044] The light source 4 is advantageously of the LED type, in order to be able to have reduced consumption and possibly light emission with different colors.

[0045] For example, the following operating modes can be provided: a power supply to the light source 4 with a high electrical power level of at least 240mW, in order to have good brightness on uneven terrain. It is also possible to provide a power supply for the light source 4 with a low electrical power level of at most 135mW, in order to increase the battery life.

[0046] By means of the switch 5, the power supply circuit 6 can advantageously switch between different operating modes:

[0047] - a standard operating mode, in which the user himself chooses different predefined brightness levels;

[0048] - an intelligent bicycle operating mode, in which the module 1 relies on the accelerometer 65 to modulate the brightness;

[0049] - an intelligent running operating mode, in which the module 1 relies on the accelerometer 65 to modulate the brightness;

[0050] - a mode called red lighting, for seeing at night with low brightness and with reduced discomfort for those close to you;

[0051] - a flashing mode, allowing you to be better seen at night, for example by flashing with a red light or with a white light;

[0052] - an energy saving mode in which the light source 4 is switched on with minimal electrical power to increase autonomy;

[0053] - an SOS mode, with the emission of the SOS light signal in Morse code, possibly with maximum brightness, to be able to be located in the event of a major problem.

[0054] The different operating modes can be identified by means of the pictograms 24, provided on the body 2 in [Fig.4].

[0055] The processing circuit 64 may have functionalities such as:

[0056] -an indication of a low battery level, by flashing the light source 4 in red. A red flash will be favored when stopped or at low speed, for example when the residual charge of the battery is less than 25%. A remaining autonomy test may be considered when the lamp is off. A number of flashes may indicate different levels of autonomy: 1 flash for 25% remaining, 2 flashes for 50% remaining, 3 flashes for 75% remaining;

[0057] -an indication of a low battery level when the light source 4 is in use, by rapid flashing of the light source 4 in white. Such rapid flashing (for example a series of 3 flashes) will be favored at high speed, so as not to reduce visibility in potentially rugged areas, for example when the residual charge of the battery is less than 10%;

[0058] - automatic switching off of the light source 4 in the event of a low battery in order to avoid damaging the battery;

[0059] - a reduction in brightness in the event of overheating of the light source 4, or a total extinction of the light source 4 in the event of greater overheating;

[0060] - switching off the light source 4 in the event of prolonged pressing of the switch 5: this makes it possible to prevent the battery from emptying in the event that the prolonged pressing is linked to an unwanted contact, for example when the module 1 is placed at the bottom of a bag.

[0061] SOS mode can be made accessible in all circumstances, even in the case of a very discharged battery: the battery safety is then deactivated. SOS mode is thus considered a priority compared to the risk of damaging the battery by excessively deep discharge.

[0062] The intelligent running mode may correspond to a second operating mode and may manage the power level increase thresholds differently. In this running mode, the processing module 64 may: d) determine and apply a third electrical power level setpoint based on the amplitude of the determined vertical acceleration; e) repeat step d) after a predetermined time.

[0063] -The light source 4 can advantageously be broken down into one or more light elements whose beam is focused in the longitudinal direction, and one or more light elements whose beam is further oriented with an inclination relative to the longitudinal direction. These different light elements can be powered independently, in order to modify the type of lighting according to the determined accelerations. The directivity of a light element can be defined by an angle relative to the longitudinal direction, beyond which the brightness has a reduced order of magnitude.

Claims

Claims

1. Lighting module (1) for a headlamp, characterized in that it comprises: - a light source (4); - an electrical power supply circuit (6) for the light source, including: a power supply interface (62) for the light source, a connection interface (61) for an electric battery, an accelerometer (65), a control circuit (63) configured to apply different levels of electrical power to the power supply interface (62), a processing circuit (64) connected to the accelerometer (65), the processing circuit (64) being configured to determine the transverse amplitude and the vertical amplitude of an acceleration of the lighting module (1) measured by the accelerometer (65) and configured to, in a first operating mode: - a) determine a first electrical power level setpoint as a function of the amplitude of the determined vertical acceleration;b) - if the amplitude of the determined transverse acceleration is greater than a first threshold, applying to the control circuit (63) a second electrical power level setpoint greater than the first setpoint; c) repeating steps a) and b) after a predetermined duration. the processing module (64) being configured to, in a second operating mode: - d) apply a third electrical power level setpoint as a function of the amplitude of the determined vertical acceleration; - e) repeating step d) after a predetermined duration; - the module further comprising a switch for selectively switching between the first and second operating modes.;

2. Lighting module (1) for headlamp according to claim 1, in which the first electrical power level setpoint is determined by the processing module (64) on a scale of at least 5 increasing power levels, the second power level setpoint being determined by increasing the first power level setpoint by 2 power levels.

3. Lighting module (1) for headlamp according to claim 1, wherein said first threshold is between 0.15 and 0.4 g.

4. Lighting module (1) for a headlamp according to any one of the preceding claims, wherein said predetermined duration is at least equal to 3 seconds.

5. Lighting module (1) for a headlamp according to any one of the preceding claims, wherein the processing circuit (64) is configured to determine the longitudinal amplitude of the acceleration of the lighting module (1) measured by the accelerometer and configured to determine the speed of the lighting module (1) by integrating the measured longitudinal amplitude, the processing circuit (4) being configured to determine the first power level setpoint also as a function of the measured longitudinal amplitude.

6. A headlamp comprising a lighting module (1) according to any one of the preceding claims.

7. Headlamp according to claim 6, comprising a front strap secured to the lighting module (1) or a velvet-hook type fixing element.

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