KR20090106994A - Three-mode integrated headlamp - Google Patents

Abstract

PURPOSE: A three-mode integrated headlamp is provided to reduce the production cost of the lighting system by easily changing the light emitting system. CONSTITUTION: A three-mode integrated headlamp is a head lamp for vehicle lighting system(100), and includes a discharge light source, a reflector, and a shutter. The reflector guides the light received from the light source to the outer side as the light ray. The shutter is mobile for the change over between the high beam mode and the downstream light ray mode about the reflector. The divergence change units(180,182) change the emissive power of the light ray between the downward/upward modes and a daytime driving illumination(DRL) mode.

Description

Triple Mode Integrated Headlamps {THREE-MODE INTEGRATED HEADLAMP}

The present invention relates to a triple mode integrated headlamp.

The present disclosure relates to a vehicle headlamp system, and more particularly to a headlamp system using a high intensity discharge lamp incorporating three different lighting functions or modes in a single assembly. Selected aspects of the present disclosure may find use in related headlamp devices, and perhaps find use outside the field of headlamps.

Vehicle discharge light sources are known in the art and are commonly referred to as xenon lamps. These discharge sources are used because of the extremely high effectiveness of the discharge lamps, not only because of their lower power consumption, but also because of the advantageous advantages of higher luminous intensity and higher brightness and increasing penetration in the vehicle lighting market.

One disadvantage of xenon lamps is associated with the high cost of the lighting system. Instead of such a lighting system, the lighting system according to the present disclosure includes a lamp, a headlamp unit (reflector, lens, etc.) and electronics for driving the lamp. The high costs associated with discharge light sources have limited the dissemination of these types of lamps in low and medium vehicle class. To some extent, an effective discharge headlamp assembly must be able to operate in multiple modes or perform multiple tasks using a single unit. Some solutions provide a separate light source between the down light application or function and the up light application or function. More recently, the so-called bi-xenon headlamp unit applies a single xenon lamp system so that a change occurs from a free upward beam operating mode without cutoff to a downward beam operating mode where the beam is cut off and mechanically the headlamp system. By switching the structure, the down light function and the up light function are realized.

U.S. Patent No. 7,029,155 teaches a car headlight capable of implementing at least two functions in a single structure: daytime running light (DRL) function / mode and infrared ray function / mode. Specifically, the reflector receives light from the high intensity discharge light source and guides the light to the light beam, with filters selectively disposed within the light path or light beam. The filter ensures that it absorbs and diffuses enough light. Thus, the headlight assembly operates in a first mode without a filter and then in a second mode where the filter is located in the path of light. In a third mode of operation, an infrared filter is optionally placed in the path of light so that only infrared light is transmitted.

In other cases, a separate incandescent light source is used to provide high intensity discharge operation in the case of downward light operation but also to provide upward light operation. Alternatively, incandescent light sources have been proposed as auxiliary light sources, which are located inside or outside the headlamp unit to implement the DRL mode of operation. It will be appreciated that the use of a separate incandescent light source, whether integrated inside the headlamp assembly or external to the headlamp assembly, still adds additional cost to the lighting system. Additional light sources also constrain the headlamp geometry and structure, increase headlamp wiring costs and limit the freedom of the structure. Thus, a bi-xenon discharge headlamp system may provide some of the solutions of a single headlamp system between an up and down light operating mode, while high intensity discharge lamps, such as discharge lamps, in particular xenon automotive lamps, may be exposed to light. It is difficult to shine. Dimming to a power level of less than 60-70% can potentially completely extinguish the arc at power levels below the design value. In addition, dimming down to the DRL operating mode, where much less light is required, simultaneously uses the same headlamp system to achieve both the down and up light operating modes, while maintaining the required level of safety in the DRL operating mode. It further exacerbates the design problem of generating low brightness in the headlamp which is still enough for the driver of the oncoming vehicle to identify.

Thus, there is a need for a photosensitive triple mode headlamp system that meets these or other needs in an efficient, effective and cost competitive manner.

The present invention provides a photosensitive triple mode headlamp system that can reduce the production cost of a lighting system and solve the problems associated with the use of a separate additional incandescent light source in an efficient, effective and cost competitive manner. For the purpose of

The photosensitive triple mode headlamp assembly uses a photosensitive discharge light source driven by an adjustable ballast / igniter unit. The light projection unit includes a first optical element for changing the light distribution for downward light application and a second optical element for changing the light distribution for DRL application involving photosensitivity.

The headlamp lighting system includes a discharge light source, a reflector for guiding light from the light source to the outside as a light beam, a shutter movable relative to the reflector for switching between the reverse light mode and the upward light mode, and the down light / up light mode and daytime running. Divergence changing means moveable between the first and second positions to change the divergence of the light beam between the illumination (DRL) modes.

The headlamp system further comprises a discharge light source dimming means for selectively dimming the discharge light source when used in the DRL mode.

The headlamp system includes a shutter that selectively blocks at least some of the light beams in the downward light mode.

The headlamp system has a shutter mounted to selectively rotate between the down light mode and the up light mode.

In a variant, the shutter selectively slides to provide a down light mode and an up light mode.

The means for changing the divergence of the light rays preferably also includes an actuator or lens for moving the light source of the reflector mirror generally in the axial direction. The lens may be mounted to selectively rotate between the down / uplight mode and the DRL mode or to selectively slide between the down / uplight mode and the DRL mode.

In a variant, the lens varies in transparency in the radial direction.

The lens may comprise a coating that varies in thickness in the radial direction.

A method of providing the down light function, the up light function, and the DRL function using a single headlamp assembly having a discharge light source comprises the steps of selectively blocking a portion of the light beam to switch between the up light function and the down light function. It includes. There is also provided a step of selectively changing the divergence of the light beam between the up / down light beam mode and the DRL mode.

Selectively dimming the discharge light source also contributes to the DRL mode.

It is a major advantage of the present disclosure to provide a single headlamp system that operates effectively in three separate modes, namely the up light mode, the down light mode and the DRL mode.

Another advantage is that it is easy to switch the system between these functions.

Another advantage is a reduction in manufacturing costs.

Another advantage is the need for less headlamp space.

Another advantage is that the lifetime of the light source is longer because it must be able to withstand a large thermal shock when the discharge light source is started. In other words, using the above-described discharge light source in all three modes, when switched on in the DRL mode and subsequently switched to the high power operating mode, the high power operating mode can be effectively implemented more quickly and with lower thermal shock.

According to the present invention, there is provided a photosensitive triple mode headlamp system which can reduce the production cost of the lighting system and solve the problems associated with the use of a separate additional incandescent light source in an efficient, effective and cost competitive manner. do.

Still other advantages and advantages of the present disclosure will become apparent upon reading and understanding the following detailed description.

1 shows a headlamp assembly 100 comprising a housing 102 surrounding a light source, preferably a high intensity arc discharge light source 104. The arc discharge light source may be any conventional arc discharge lamp suitable for vehicle lighting applications, or may be a type of HID light source as disclosed in a bixenon headlamp system as described in issued patents EP1177939B1, US5,769,525 and EP0816749B1. The above patent is cited, the details of which are incorporated herein. Light transmissive envelopes, such as quartz envelopes, surround a selectively energized fill by applying a voltage between opposingly disposed electrodes to create an arc. As shown in FIG. 1, in a preferred embodiment, the electrodes are generally aligned along a longitudinal axis that coincides with the longitudinal axis of the housing, more specifically along the reflector surface 106. However, the arrangement or arc direction of these electrodes may be different in some particular lamp structures. The reflector surface is generally a rotating surface, for example a parabolic surface, an ellipsoidal surface, or other spherical surface, which may or may not be distorted to be non-rotational symmetric, or may or may not be cut as shown by plane 108. The reflector receives the light emitted from the light source 104 and guides the received light outward in the desired direction to form a light beam. For example, it is important that such light does not contain dazzling light directed at oncoming drivers, and the specific light pattern is usually determined by existing regulations.

As can be appreciated, using current high intensity discharge light sources for vehicle lighting, the light sources provide 2700 to 3600 lumens for down light and up light operation. The output of the light source itself does not change between these two modes of operation. Rather, an opaque shutter as shown herein is used as the shutter 120 to control the light output from the lighting system. Such a shutter is mounted to the housing to selectively rotate about the axis 122 and, when rotating fully upwards in the direction indicated by the reference arrow 124, approximately covers the lower half of the opening 126 in the housing. Thus, if the shutters are placed in place, approximately half of the light from the discharge light source is effectively blocked from exiting the housing. Thus, the headlamp assembly effectively operates in the down light mode when the shutter is in the upright or actuated position. When the vehicle driver requires upward beam operation, the upward beam operation mode is implemented by moving the shutter 120 to an inoperative position or an inactive position using the full opening 126 to provide the beam. In the current model of the bi-xenon reflector, the single metal shutter acts as an optical switch between the up and down light modes. Upon switching, this metal shutter plate moves up and down to block nearly half of the light in the down light mode and allow the entire light to pass through the front lens 130 in the up light mode. It will also be appreciated that the up / down beam shutter 120 may be a shutter that is pulled out of the beam or pushed into the beam by an actuator, i.e. with sliding motion.

To switch to DRL mode, the light divergence or light intensity distribution must also be changed. To achieve this, those skilled in the art will understand that the light source can be moved relative to the reflector. This is one way to "blur" the light source for the reflector, thus changing the light output angle from the discharge lamp. Moving the light source in the axial direction to change the light beam and allow it to diverge further poses more difficult design challenges for the technician and the manufacturer. On the other hand, as shown in FIG. 1, the lens may optionally be disposed in the light path. In this case, the first lens portion 140 and the second lens portion 142 are rotatably mounted to the housing. But it indicates that the lens portion is a closed relationship to the opening 126 in the housing to move in a predetermined direction in which the pivot and wherein the shutter is arranged around a respective axis 146 by the reference numeral 144, these lens part 1 It is shown in an open structure. When the first lens portion and the second lens portion are operated across the light output from the headlamp to a position to close the opening 126, the dividing line 148 is present between the first lens portion and the second lens portion. do. As shown herein, these lens portions are two mating halves that are rotated in place. Alternatively, the lens may also be a single lens or a one-piece lens, or more than two lens portions may be used to defocus the beam and increase the divergence of the beam. The lens is intended to be made of a transparent material so as not to lose significant light energy. For the use of headlamps in DRL mode only slightly changes the beam divergence. For example, it may be desirable to coat the lens surface with a material that varies in thickness and varies radially. For example, increasing the thickness of the coating at the edges degrades the transparency of the lens adjacent to the edges of the lens. In optics, this is called apodization and is effectively used to reduce light diffraction from the edge of the lens. In any case, a transparent coating on the lens can be used to alter the intensity distribution of the light beam, thus meeting the regulatory requirements for DRL light divergence and intensity requirements.

As mentioned above, the degree of ray divergence can also be altered by moving the large front lens 130 in the axial direction to defocus the ray. This has the same effect as moving the light source out of focus or moving the mirror axially with respect to the light source to intentionally bring the light source out of focus again. In the case of using an additional lens, the lens is usually a diverging lens, i.e. a concave lens or a light beam whereas a half lens is introduced, and the embodiment of Fig. 1 or the variant of Figs. 2-4 can be used. In addition, it is possible to blur the focus by using three separate lens elements, where at least one of the lens elements moves relative to the other two lenses, as used in conventional zoom lens systems. For example, one of the lenses may be the front lens 130 of the reflector. The focus is then blurred by moving the center lens relative to the other two lenses or by moving the first and third lenses relative to the second lens fixed in the system and changing the effective focal length of the zoom lens system.

As shown in FIG. 2, the shutter 158 is shown schematically, while focusing on an alternative structure of the lens. Lenses 160 and 162, on the other hand, are selectively rotated around the respective axis 166 in the direction indicated by arrow 164. At this time, the axis 166 is disposed generally in the horizontal direction or at 90 ° with respect to the axis 146 of the embodiment of FIG. 1. In substantially all other aspects, the structure and operation of FIG. 2 are the same as the embodiment of FIG. Once fully rotated into the path of the light beam, dividing line 168 is formed between the lens portions. Also consider that the second or lower lens portion 162 is a shutter that effectively blocks light output from the lower semicircle portion of the opening 126. Since light is emitted only through the upper half of the aperture, only the first or upper lens portion 160 needs to be selectively introduced into the light beam to change the divergence of the light for DRL mode operation.

3 is another embodiment in which the first lens portion 180 and the second lens portion 182 are configured to selectively slide in a path of light. In this particular case, the directional arrow 184 indicates that the first lens portion 180 and the second lens portion 182 operate to move in a neighboring relationship along the separation line 186. In addition, the shutter 188 is optionally rotated as indicated by the directional arrow 190 to again block the lower semicircle portion of the opening for downward ray operation. As can be appreciated, in the upward ray mode, the shutter 188 moves out of ray and does not affect light output. In addition, in the DRL mode, the shutter 188 rotates upward to block a substantial portion of the light output through the opening 126, and the lenses 180 and 182 are arranged to change the divergence of the light beam.

4 is for changing the divergence in the DRL mode by moving the single lens 200 in the axial direction. Thus, in the first or leftmost portion 202 as shown in FIG. 4, the lens provides the divergence required for the upward ray mode. For the down light mode, the shutter 204 rotates upward in the path of the lower semicircular portion of the opening 126 of the headlamp housing as indicated by the directional arrow 206. In the activated shutter position, the headlamps then operate in downward light mode. For the third mode or DRL mode, the lens 200 moves to the second or right position 208. In addition, the shutter 204 can also move upward to reduce the amount of light exiting the headlamp assembly.

Alternatively, FIG. 4 may also be a typical zoom lens system as described above. That is, reference numeral 202 may refer to the first lens, reference numeral 208 may refer to the movable lens portion, and the outer lens 210 may serve as the third lens of the assembly. That is, the first lens 202 and the third lens 210 remain fixed at a predetermined position, while the intermediate lens 208 changes the focus or divergence of the light output.

The intensity of light required for the upstream light mode, the downlight light mode, and the DRL mode can be expressed in various physical units. For example, the curve in FIG. 5 illustrates lamp power versus lamp lumens when the HID vehicle lamp is sensitized to the same luminous flux level as currently used incandescent lamps for DRL applications. Dimmed light levels of 300 to 400 lumens are effective for the DRL mode of operation. Lumen levels between 2700 and 3600 lumens are used for both upward and downward ray applications. However, it should be noted that the required lumen level depends on the reflector structure. That is, both the efficiency and geometry of the reflector affects the reflector structure and can change the lumen level required for a particular headlamp assembly. Alternatively, the light levels in the up light mode and in the down light mode are also given in lux, which is a brightness unit representing the brightness intensity (watts per square meter (watts / m 2)) of the reference screen. For the chandelier beam, the center of the beam is the brightest part, which must meet the 100 lux unit requirement according to current standards. In the down light mode, the luminance distribution is more complex and several points on the reference screen are defined. Some of these points have the lowest lux value, i.e. when the driver wants to see the road, while others have the highest lux value in the direction of the oncoming traffic. In the DRL mode, the light intensity has an appropriate physical size, which is specified in candelas. In other words, the purpose of the DRL mode is not to illuminate the road surface in front of the vehicle, but to allow a vehicle using DRL mode headlamp operation to be detected by other vehicles in the vehicle flow.

In summary, a high intensity discharge lamp based automotive headlamp system is provided that includes three different lighting functions integrated into a single headlamp unit. The electronics for driving the photosensitive discharge lamp can also be used to reduce the power output of the lamp in the DRL mode. The three functions are downward light, upward light and daytime running light, all of which provide the required light output, divergence and intensity using the same headlamp assembly with a series of shutters and lens (s). Movement among these three modes is facilitated by changing the position of the lens or shutter, ie sliding or rotating between the operating position and the non-operating position. The light distribution is thus effectively changed, resulting in an additional DRL light distribution in standard up / down light operation or in a third mode of operation.

Additionally, by adjusting the ballast electrical output to achieve up / down light or DRL light distribution and intensity, the illumination output may be photosensitive in a wide range of light sources. This solution avoids using a separate incandescent or halogen incandescent light source, which is often proposed as an auxiliary light source for use inside or outside the headlamp unit for the DRL mode of operation. Thus, the light projection unit features two optical elements. The first optical element changes the light distribution for downward light applications, while the second optical element changes the light distribution for DRL applications involving photosensitivity. The DRL light distribution mode is achievable by using additional lenses that are used and moved in various modes. The lens can optionally rotate in the projected light path or can selectively slide in the projected light path. Alternatively, the lens is moved in the axial direction of the projected light path. Using a linear actuator, the light source can also be moved out of the position of the up and down light operating modes so that a modified light distribution is formed.

Since the light source is always switched on for all three modes, the light source is warmed up and can be easily switched to a higher power operating mode with less thermal shock. When the lens is moved in the projected light path, a simple actuator can move the lens axially or rotate the lens portion (s) to a predetermined position. Similarly, electromagnetic actuators or piezoelectric translators can be used to achieve this function.

The present invention has been described with reference to preferred embodiments. It is clear that modifications and variations are possible in light of the above detailed description. It is to be understood that the present invention includes all such modifications and variations.

1 is a perspective view of a first preferred embodiment of a headlamp system;

FIG. 2 is similar to FIG. 1 but with the lens portion rotating in the opposite direction.

3 is a perspective view of another embodiment in which the shutter rotates and the lens optionally slides to a predetermined position.

4 is an elevational view of a fourth preferred embodiment in which the shutter is selectively rotatable and the lens is axially movable;

5 graphically illustrates lamp power against lumens associated with high intensity discharge lamps.

<Explanation of symbols for the main parts of the drawings>

100: Headlamp Lighting System

104: discharge light source

106: reflector

120, 158: Shutter

200 lens

Claims (10)

As a vehicle headlamp lighting system 100, Discharge light source 104, A reflector 106 for guiding the light received from the light source to the outside as a light ray, A shutter 158 movable relative to the reflector for switching between the down light mode and the up light mode; Divergence changing means (200, 180/182) moveable between the first and second positions to change the divergence of the light beam between the down / up beam mode and daytime running light (DRL) mode. Automotive headlamp lighting system. The vehicle headlamp lighting system according to claim 1, further comprising a discharge light source dimming means for selectively dimming the discharge light source when the system is used in the DRL mode. 3. The headlamp lighting system for a vehicle according to claim 2, wherein said discharge light source dimming means includes adjusting means for adjusting a lamp luminous flux when switching between an upward light beam mode and a downward light beam mode. 4. The headlamp lighting system for a vehicle according to claim 3, wherein said discharge light source photosensitive means includes means for changing light intensity. The vehicle headlamp lighting system of claim 1, wherein the shutter (120) selectively blocks at least a portion of the light beams in the downward light mode. The vehicle headlamp lighting system of claim 1, wherein the shutter (120) is mounted to selectively rotate between the down light mode and the up light mode. The vehicle headlamp lighting system of claim 1, wherein the shutter (120) is mounted to selectively slide between the down light mode and the up light mode. 2. A headlamp lighting system for a vehicle according to claim 1, wherein the means for changing the divergence of the projected light rays comprises a lens (200). 10. The vehicle headlamp of claim 8, wherein the lens is mounted to perform one of selective rotation between the down / up beam mode and the DRL mode and selective sliding movement between the down / up beam mode and the DRL mode. Lighting system. Down light function, up light function, and daytime running for an automotive headlamp assembly 100 having a discharge light source 104 for emitting light and a reflector 106 for guiding light emitted from the light source to the required light beams. As a method of providing the lighting (DRL) function, Selectively blocking a portion of the light beam to switch the headlamp assembly between the up light function and the down light function, and Selectively changing the divergence of the light beam between the up / down light mode and the DRL mode.

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