JP2017111938A - Vehicle headlamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle headlamp capable of melting and removing snow attached to an outer lens without causing loss of a luminous flux.SOLUTION: A vehicle headlamp 1 accommodates at least one of a lamp 5 for main beam and a lamp 6 for low beam in a lamp chamber 4 defined by a housing 2 and an outer lens 3 for covering a front opening part. Fin-shaped heating elements 14 protruding substantially in parallel with an optical axis toward a vehicle front are arranged along the width direction, above or below or both above and below the optical axis x of at least one of the lamp 5 for main beam and the lamp 6 for low beam of an outer surface the outer lens 3. Here, the heating element 14 is constituted by arranging a planar heater 14b on an upper surface of a base material 14a made of a shape memory material. Between a rear end surface of the heating element 14 and the outer surface of the outer lens 3, a gap δ along the width direction may be formed.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a vehicle headlamp that melts and removes snow and ice attached to an outer lens.

  As shown in FIG. 11, when snow adheres to the outer lens 103 of the headlamp 101 of the vehicle 50 during rainfall or snowfall, the luminous flux emitted from the headlamp 101 is reduced or the light distribution is disturbed. The problem that normal function is impaired occurs.

  In order to solve the above problem, for example, in Patent Documents 1 and 2, a transparent electrically insulating sheet-like member on which a conductive pattern is printed is fixed to the outer lens surface by in-mold or the like, and the conductive property of the sheet-like member is determined. There has been proposed a configuration in which the conductive pattern is heated by supplying power to the pattern, and the outer lens is heated by this heat to melt and remove snow and ice attached to the surface of the outer lens.

JP 2007-026989 A JP 2008-052919 A

  However, in the configurations proposed in Patent Documents 1 and 2, there is a problem that the sheet-like member fixed to the outer lens causes a loss of light flux from the headlamp, and the illuminance of the headlamp decreases.

  The present invention has been made in view of the above problems, and an object thereof is to provide a vehicular headlamp that can melt and remove snow attached to an outer lens without loss of light flux. is there.

  To achieve the above object, according to the first aspect of the present invention, at least one of a traveling beam lamp and a passing beam lamp is accommodated in a lamp chamber defined by an outer lens covering a housing and a front opening of the housing. In the vehicle headlamp, the optical axis toward the front of the vehicle above or below or above and below the optical axis of at least one of the traveling beam lamp or the low beam lamp on the outer surface of the outer lens. And a fin-like heating element protruding substantially in parallel with each other along the width direction.

  According to a second aspect of the present invention, in the first aspect of the present invention, the heating element is configured by disposing a planar heater on an upper surface of a base material made of a shape memory material.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, a gap along the width direction is formed between a rear end surface of the heating element and an outer surface of the outer lens.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, fixing pins that protrude substantially horizontally toward the front of the vehicle are respectively fixed to the two left and right fixed receiving portions fixed to the vehicle body. The fixing pins are used to support both ends in the width direction of the heating element from the back side, and the fixing pins are used as a power feeding path to the heating element.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, and the invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the temperature of the heating element is And a control means for turning on and off the heating element based on the temperature detected by the temperature detection sensor.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the outer surface of the outer lens is coated with a fluororesin.

  According to the first aspect of the present invention, the snow adhering to the heating element can be melted by the heat generated by the heating element to generate snowmelt water, and the snow adhering to the outer lens can be melted and removed by the snowmelt water. For this reason, a decrease in the luminous flux of the headlamp due to the attachment of snow to the outer lens is prevented. When the vehicle is traveling, the snowmelt water is moved or scattered from the heating element to the outer lens by the traveling wind to melt the snow attached to the outer lens. Here, since the heating element has a fin shape, the aerodynamic performance of the vehicle is not hindered, and the heating element is disposed above or below or above and below the optical axis of the outer surface of the outer lens. The luminous flux of the headlamp is not obstructed by the heating element, and the required illuminance is ensured for the headlamp.

  According to the second aspect of the present invention, since the heating element is configured by arranging the planar heater on the upper surface of the base material made of the shape memory material, the heating element is restored even if the heating element is deformed by an external force. Thus, the function of the heating element is not deteriorated by deformation.

  According to the third aspect of the present invention, the snowmelt water generated by the heating element passes along the gap formed between the rear end surface of the heating element and the outer surface of the outer lens and falls along the outer surface of the outer lens by its own weight. Therefore, the snow adhering to the outer surface of the outer lens is efficiently melted by the melted water. For this reason, snow can be melted even when the vehicle is stopped or traveling at a low speed, and the melted water or the sherbet-like snow being melted can be discharged from the outer lens through the gap.

  According to the fourth aspect of the invention, the heating element is supported on the vehicle body by the left and right fixing pins, whereby a predetermined gap can be formed between the heating element and the outer lens, and the fixing pin is heated. By using it as a power feeding path to the body, the power feeding structure can be simplified.

  According to the fifth aspect of the invention, the heating element is controlled to be ON / OFF based on the temperature detected by the temperature detection sensor, so that the temperature of the heating element is suppressed to a predetermined value or less and the heating element is excessively heated. Can prevent temperature.

  According to the invention described in claim 6, since the outer surface of the outer lens 3 is coated with the fluororesin, it is possible to prevent the dirt from adhering to the outer surface, and also to prevent snow accretion and to collect snow melt water on snow accretion It is possible to improve the efficiency of melting snow, and the ability to discharge snowmelt water and sherbet-like snow can also be improved.

1 is a half-cut front view of a vehicle including a vehicle headlamp according to the present invention. It is a side view of the vehicle front part provided with the vehicle headlamp which concerns on this invention. It is a half-cut top view of the vehicle front part provided with the vehicle headlamp which concerns on this invention. It is the sectional view on the AA line of FIG. It is a partial side view explaining the snow melting mechanism in the outer lens surface. (A), (b) is a perspective view of the headlamp which shows the example of arrangement | positioning of a heat generating body. It is a block diagram which shows the structure of the control system of the vehicle headlamp which concerns on this invention. It is a flowchart which shows the control procedure of the vehicle headlamp which concerns on this invention. It is a fragmentary sectional side view of the vehicle headlamp which shows another form of this invention. FIG. 10 is a sectional view taken along line B-B in FIG. 9. It is a side view of the vehicle front part explaining the fall of the light beam by the snow landing on the outer lens of the vehicle headlamp.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 is a half cut front view of a vehicle equipped with a vehicle headlamp according to the present invention, FIG. 2 is a side view of the vehicle front portion, FIG. 3 is a half plan view of the vehicle front portion, and FIG. FIG. 5 is a partial side view for explaining the snow melting mechanism on the surface of the outer lens, and FIGS. 6A and 6B are perspective views of a headlamp showing an example of arrangement of heating elements.

  A vehicle 50 shown in FIGS. 1 to 3 includes a headlamp 1 (only one is shown in FIGS. 1 to 3) according to the present invention on the left and right of the front part of the vehicle body. Here, since the basic configurations of the left and right headlamps 1 are the same, only one headlamp 1 will be illustrated and described below.

  Each headlamp 1 is disposed in a lamp chamber 4 defined by a housing 2 shown in FIG. 4 and a transparent outer lens 3 covering the front opening thereof, and on the outer side in the vehicle width direction as shown in FIGS. The traveling beam (high beam) lamp 5 and the passing beam (low beam) lamp 6 disposed on the inside thereof are accommodated.

  Here, a specific configuration of the low beam lamp 6 is shown in FIG. 4. In the low beam lamp 6, a solid light source (for example, a light emitting diode (LED) or a laser as a semiconductor light emitting element) 7 is provided. A phosphor 9 and a projection lens 10 are sequentially arranged in front of the laser light source 7 (left side in FIG. 4). An extension 11 is disposed around the low beam lamp 6, and the solid-state light source 7 is electrically connected to a power source 12 disposed on the lower surface of the housing 2 via a power supply wiring 13. Yes.

  Thus, in the present embodiment, as shown in FIG. 4, the front of the vehicle is positioned above and below the optical axis x of the traveling beam lamp 5 and the passing beam lamp 6 on the outer surface of the outer lens 3 of the headlamp 1. Fin-like heating elements 14 projecting substantially parallel to the optical axis x toward the left (in FIG. 4) are arranged along the width direction. Here, as shown in FIG. 5, each of the upper and lower heating elements 14 is configured by disposing a planar heater 14b on the upper surface of a base material 14a made of a shape memory material. Here, as the shape memory material constituting the base material 14a, nickel / titanium alloy, copper / zinc / aluminum shape memory alloy, reinforced plastic (CFRP, GFRP) including carbon fiber and glass fiber having high shape recoverability Etc.), highly transparent acrylic, PET (polyethylene terephthalate) and the like are used. The planar heater 14b generates heat when energized. For example, a nickel / chromium alloy, a carbon thin film or wire, an indium tin oxide thin film, or the like is used. In addition, the heater 14b of each heat generating body 14 is electrically connected to the power source 12 via a power supply wiring (not shown).

  Here, examples of arrangement of the upper and lower heating elements 14 on the outer lens 3 are shown in FIGS. 6A and 6B. These heating elements 14 are formed on the outer surface of the outer lens 3 as shown in FIG. Are arranged so as to be substantially parallel in the vertical direction, or are arranged so as to open up and down toward the outer side of the outer lens 3 as shown in FIG. Note that the arrangement shown in FIG. 6B is advantageous in terms of aerodynamic characteristics in which snow and ice melted while the vehicle is traveling are efficiently scattered from the outer lens 3.

  Next, the configuration of the control system for the headlamp 1 according to the present invention will be described with reference to FIG.

  FIG. 7 is a block diagram showing a control system for the headlamp 1 according to the present invention. A storage unit 15a is built in the ECU 15 which is a control means, and on the input side of the ECU 15, a snow melting switch 16 and A temperature detection sensor 17 and a snowfall sensor 18 are connected, and a heating element 14 is connected to the output side. Note that the snow melting switch 16 is an ON / OFF operation by the occupant by his / her own intention. Moreover, the snowfall sensor 18 detects snowfall by the presence or absence of the reflection by a laser beam, for example.

  Next, the operation of the headlamp 1 according to the present invention will be described below with reference to the flowchart shown in FIG.

  For example, when the vehicle travels under snowfall or when snow or ice adheres to the outer lens 3 of the headlamp 1 of the parked vehicle 50, the occupant who has entered the vehicle 50 turns the snow melting switch 16 on. Turns on (step S1: Yes in FIG. 8). Then, ECU15 determines whether the temperature of the heat generating body 14 detected by the temperature detection sensor 17 is 40 degrees C or less (step S2 of FIG. 8). If the result of this determination is that the temperature of the heating element 14 is 40 ° C. or lower (step S2: Yes), the heating element 14 is energized from the power supply 12 via a power supply wiring (not shown) and turned on ( Step S3).

  When the heating element 14 is energized as described above, the heater 14b of the heating element 14 generates heat, and as shown in FIG. The generated snow (snow accretion) attached to the outer lens 3 is melted and removed by the melted water. For this reason, a decrease in the luminous flux of the headlamp 1 due to the attachment of snow to the outer lens 3 is prevented. When the vehicle 50 is traveling, the snowmelt water moves or scatters from the heating element 14 to the outer lens 3 by the traveling wind, and melts the snow attached to the outer lens 3. Here, since the heating element 14 has a fin shape, it does not hinder the aerodynamic performance of the vehicle 50 and is disposed vertically with respect to the optical axis x of the outer surface of the outer lens 3. The heating element 14 does not obstruct the luminous flux of the headlamp 1, and a required illuminance is ensured for the headlamp 1.

  In addition, when the outer surface of the outer lens 3 is coated with a fluororesin, it is possible to prevent dirt from adhering to the outer surface, to prevent snow accretion, and to improve snow melting efficiency by condensing snow melt water on the snow accretion. This also improves the discharge of snowmelt water and sherbet-like snow. Here, the fluororesin can be coated by, for example, spray coating and heat curing treatment.

  Further, in the present embodiment, since the heating element 14 is configured by arranging the planar heater 14b on the upper surface of the base material 14a made of a shape memory material, even if the heating element 14 is deformed by an external force, the heating element 14 is deformed. However, the function of the heating element 14 is not deteriorated by deformation.

  By the way, it is known that when the moisture content of the snow attached to the outer lens 3 becomes 35% or more, the snow structure cannot be maintained, and the snow slides along the surface of the outer lens 3 by its own weight. Here, since the moisture content of the snow is usually about 15%, if 20% or more of the snow adhering to the surface of the outer lens 3 is melted, the snow can be slid down by its own weight. However, in actuality, since the amount of snow melted by the vehicle body is added to the snow attached to the outer lens 3, even if the snow melting rate is less than 20%, the snow slides along the surface of the outer lens 3. It becomes possible to make it.

  The ECU 15 determines whether or not the temperature of the heating element 14 detected by the temperature detection sensor 17 exceeds a predetermined value (for example, 60 ° C.) after the heating element 14 is energized and turned on (FIG. 5). 8 step S5). As a result of this determination, when the temperature of the heating element 14 exceeds a predetermined value (60 ° C.) (step S5: Yes), the energization to the heating element 14 is cut off and turned off (step S6). Thereafter, each process described above is repeated (step S7). For this reason, the temperature of the heating element 14 is suppressed to a predetermined value (60 ° C.) or less, and excessive heating of the heating element 14 is prevented. Incidentally, when the material of the base material 14a of the heating element 14 is acrylic, the deformation strain relaxation temperature of acrylic is 80 ° C., so that the temperature of the heating element 14 does not exceed 60 ° C. as in the present embodiment. It is necessary to.

  Next, another embodiment of the present invention will be described below with reference to FIGS.

  9 is a partial sectional side view of a vehicle headlamp showing another embodiment of the present invention, and FIG. 10 is a sectional view taken along the line BB of FIG. 9. In this embodiment, the rear of the upper and lower heating elements 14 is shown. A gap δ of about 2 to 10 mm along the width direction is formed between the end surface and the outer surface of the outer lens 3. Specifically, fixing pins 20 that protrude substantially horizontally toward the front of the vehicle are respectively fixed to the left and right fixing receiving portions 19 fixed to the vehicle body of the vehicle 50, and the heating element 14 is fixed by the left and right fixing pins 20. By supporting both ends in the width direction from the back side, a gap δ along the width direction can be formed between the rear end surfaces of the upper and lower heating elements 14 and the outer surface of the outer lens 3. In this case, the left and right fixing pins 20 are used as a power feeding path to the heating element 14. In the present embodiment, the power supply wiring is passed through the fixed pin 20.

  Thus, according to the present embodiment, the snowmelt water generated by the heating element 14 passes through the gap δ formed between the rear end surface of the heating element 14 and the outer surface of the outer lens 3, and the outer lens is caused by its own weight. Therefore, the snow adhering to the outer surface of the outer lens 3 is efficiently melted by the melted snow water. For this reason, snow can be melted even when the vehicle 50 is stopped or traveling at a low speed, and the snow melt water or the sherbet-like snow being melted can be discharged from the outer lens 3 through the gap δ.

  In the present embodiment, the heating element 14 is supported on the vehicle body by the left and right fixing pins 20, whereby a predetermined gap δ can be formed between the heating element 14 and the outer lens 3, and the fixing pin By using 20 as a power supply path to the heating element 14, an effect that the power supply structure can be simplified is obtained.

  In the above embodiment, the two upper and lower heating elements 14 are arranged above and below the optical axis x. However, one heating element 14 may be arranged above or below the optical axis x.

DESCRIPTION OF SYMBOLS 1 Vehicle headlamp 2 Housing 3 Outer lens 4 Lamp chamber 5 Traveling beam lamp 6 Passing beam lamp 7 Solid light source 8 Heat sink 9 Phosphor 10 Projection lens 11 Extension 12 Power supply 13 Power supply wiring 14 Heating element 14a Base of heating element Material 14b Heater heater 15 ECU (control means)
16 Snow melting switch 17 Temperature detection sensor 18 Snowfall sensor 19 Fixed receiving portion 20 Fixed pin 50 Vehicle x Optical axis δ Clearance between heating element and outer lens

Claims (6)

In a vehicle headlamp configured to house at least one of a traveling beam lamp or a low beam lamp in a lamp chamber defined by an outer lens covering a housing and a front opening thereof,
Fin-like heat generation that protrudes substantially parallel to the optical axis toward the front of the vehicle above or below or above and below the optical axis of at least one of the traveling beam lamp and the low beam lamp on the outer surface of the outer lens. A vehicle headlamp characterized in that a body is arranged along a width direction.   The vehicle headlamp according to claim 1, wherein the heating element is configured by arranging a planar heater on an upper surface of a base material made of a shape memory material.   The vehicular headlamp according to claim 1 or 2, wherein a gap along a width direction is formed between a rear end surface of the heating element and an outer surface of the outer lens.   Fixing pins that protrude substantially horizontally toward the front of the vehicle are respectively fixed to the two left and right fixed receiving portions fixed to the vehicle body, and both the widthwise ends of the heating element are supported from the back side by the left and right fixing pins. The vehicle headlamp according to claim 3, wherein the fixing pin is used as a power feeding path to the heating element.   The temperature detection sensor which measures the temperature of the said heat generating body was provided, and the control means which turns ON / OFF the said heat generating body based on the temperature detected by this temperature detection sensor was provided. The vehicle headlamp according to any one of the above. 6. The vehicular headlamp according to claim 1, wherein an outer surface of the outer lens is coated with a fluororesin.

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