JP4565653B2 - LED lights for vehicles - Google Patents

Description

  The present invention relates to a vehicle LED lamp using an LED as a light source.

  Some vehicle lamps, like rear combination lamps, have four lamp units, a tail lamp unit, a stop lamp unit, a back lamp unit, and a turn signal lamp unit, in one lamp (in the lamp chamber). Each lamp unit is provided with a light source, a reflector, a lens, and the like.

  In this case, the rear combination lamp composed of four independent lamp units imposes structural restrictions on the demand for miniaturization and restricts the degree of design freedom.

  Also, when designing one rear combination lamp, it is necessary to individually design reflectors, lenses, etc. constituting each lamp unit, which increases design man-hours, and increases the number of parts in manufacturing. As a result, mold costs and material costs increase.

  In recent years, LEDs have been gradually adopted as light sources for vehicle lamps, and high-mount stop lamps, stop lamps, tail lamps, turn signal lamps, and the like have already been put into practical use. An LED light source is generally driven (lit) by mounting a plurality of LEDs on a single circuit board, wiring in a matrix circuit configuration as shown in FIG. 6, and applying a voltage.

  In this case, if a problem such as short or open occurs in at least one LED and the need for replacement occurs, all the LEDs are mounted on one circuit board, so that the entire circuit board must be replaced. Thus, the cost of parts replacement is expensive.

  In addition, when the electrical characteristics (particularly the forward voltage) of at least one LED are different from those of other LEDs, the circuit configuration also affects the brightness of the other LEDs, resulting in a light source with large variations in brightness. End up. Therefore, when mounting on the circuit board, it is necessary to select the electrical characteristics in advance, which increases the manufacturing cost.

  As a vehicular lamp using an LED as a light source, a tail lamp 50 as shown in FIG. 7 has been proposed. It includes a housing 53 consisting of a cylindrical portion 51 and a bottom portion 52 and an outer lens 54. A plurality of LEDs 55 are mounted on the inner surface of the cylindrical portion 51 along the circumferential direction, and the bottom portion 52 focuses on each LED. The reflector surface 56 has a shape in which parabolas are gathered in the circumferential direction.

The light emitted from each LED 55 is reflected by the reflector surface 56 to become parallel light, and the light distribution is controlled by the outer lens 54 to irradiate the front of the lamp (for example, see Patent Document 1).
JP 2005-78938 A

  In the vehicle lamp described above, the reflector surface 56 has only a function for directing the light emitted from each LED 55 as the parallel light in the direction of the outer lens 54, and the light emitted toward the lamp from the outside. It does not have a function as a retroreflective surface for returning to the outside again. Therefore, in order to give the vehicle a retroreflective function, it is necessary to separately install a retroreflector in a place other than the vehicle lamp.

  Further, since the configuration of such a lamp is not provided with optical path control means for controlling the optical path of the light emitted from the LED in units of LED groups, for example, different light distribution characteristics such as a tail lamp and a back lamp are different. It is impossible to integrally form a plurality of lamp units that require color tone irradiation light.

  Therefore, the present invention was devised in view of the above problems, and the object of the present invention is to realize a plurality of lamps which realize miniaturization and increase the degree of freedom in design, and have different light distribution characteristics or color tone of irradiation light. An object of the present invention is to provide a vehicular LED lamp having a unit integrated structure and a retroreflective function.

  In order to solve the above-mentioned problems, an invention described in claim 1 of the present invention is a vehicle LED lamp in which a plurality of LEDs serving as a light source are disposed in a lamp chamber formed by a lens and a housing. In addition, a prism lens having a sawtooth cross-section in which a plurality of triangular prisms having apex angles in the direction of the lamp chamber are formed substantially in parallel is formed on the lamp chamber side of the lens, and the triangular prisms sandwiching the triangular prisms The plurality of LEDs are arranged on the respective side surfaces of the LED with the optical axis of the LEDs directed toward the triangular prism.

  According to a second aspect of the present invention, in the first aspect, the LED light reflected on one side surface common to each triangular prism formed on the prism lens and the other common to each triangular prism are provided. The LED light reflected from the side surfaces of the light beam constitutes an optical system different from each other, and the light incident from the outside into the lamp is sequentially reflected on both side surfaces of the triangular prisms and then recursively reflected outside the lamp. The optical system is configured as follows.

  According to a third aspect of the present invention, in any one of the first and second aspects, at least a part of each side surface of each triangular prism formed on the prism lens is a half mirror. A film or a metal film is formed.

  The invention described in claim 4 of the present invention is the LED disposed on one side face common to each triangular prism formed in the prism lens in any one of claims 1 to 3. The LEDs disposed on the other side face common to the triangular prisms emit light having different wavelengths.

  The vehicular LED lamp according to the present invention forms a prism lens having a sawtooth cross section in which a plurality of triangular prisms having apex angles directed in the direction of the lamp chamber are formed substantially in parallel on the lamp chamber side of the lens serving as a lamp chamber forming member. A plurality of LEDs are arranged on the side surfaces of the triangular prisms sandwiching the triangular prisms with the optical axis of the LEDs directed toward the triangular prisms.

  The LED light reflected on one side surface common to each triangular prism formed in the prism lens and the LED light reflected on the other side surface common to each triangular prism constitute different optical systems, respectively. The light that entered the lamp from the outside is sequentially reflected on both side surfaces of each triangular prism, and is configured to form a retroreflective optical system that is emitted outside the lamp again.

  As a result, a plurality of retroreflector lamp units such as tail lamps, stop lamps, back lamps, and vehicle rear-viewing camera illumination light sources, etc., which are different in light distribution characteristics or color tone of the irradiated light, are integrated and retroreflected. In addition, an LED lamp for a vehicle having a higher degree of design freedom by downsizing can be provided.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIG. 1 to FIG. 5 (the same reference numerals are given to the same portions). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  FIG. 1 is a perspective view showing an embodiment of an LED lamp for a vehicle according to the present invention. Among members constituting the lamp, an LED serving as a light source and a lens for controlling the light distribution of the light emitted from the LED light source; This shows the relationship.

  The lens 1 is made of a light-transmitting material, and when the lamp is configured, the surface that becomes the outside (outside of the passenger compartment) of the lamp is formed as a flat surface 2, and there are many surfaces that become the inside (lamp side) of the lamp. A prism lens surface 4 having a sawtooth cross-section in which the prisms 3 are formed substantially parallel to each other.

  The flat surface 2 on the outside of the lamp of the lens 1 is designed based on the design of the lamp, and is formed into a flat surface, a quadric surface, a cubic surface, or the like. Therefore, the flat surface 2 is a surface corresponding to the bottom surface 5 of each prism 3, and the apex angle 6 of each prism 3 is directed toward the lamp chamber.

  The LED 7 serving as a light source is mounted in a package in which an LED bare chip (not shown) serving as a light emitter is sealed with a transparent resin, and the emission color of the LED bare chip is based on the lamp function that the lamp has. It is decided appropriately. Further, the shape of the LED 7 package is also determined in consideration of the required light distribution characteristics, the arrangement space, and the like.

  Then, a plurality of LEDs 7 are arranged substantially linearly at a predetermined interval with respect to each side surface 8 of each prism 3 and the emission direction of the LED 7 light (the optical axis direction of the LED 7) faces the side surface 8 of the prism 3. It is installed.

  FIG. 2 is a diagram showing an optical path of light emitted from the LED light source and light emitted from the outside of the lamp toward the lamp. The vehicular LED lamp according to the present invention includes three optical systems, and each optical system performs an individual function.

  In the optical system shown in FIG. 2A, the light emitted from the LED 7 disposed on the same side surface 8a side of each prism 3 of the lens 1 forming the lamp chamber together with the housing 9 is opposed to the other side surface 8a. Light that is introduced into the prism 3 toward the side surface 8b, is guided through the prism 3 to the other side surface 8b that faces the surface 8, is reflected (totally reflected) by the side surface 8b, and travels toward the bottom surface 5 in the prism 3. Is guided to the bottom surface 5 to form an optical path that is emitted from the bottom surface 5 to the outside of the lamp 10.

  In this case, the light emitted outside the lamp 10 is irradiated in a direction substantially horizontal to the vehicle in a state where the lamp 10 is mounted on the vehicle. Therefore, for example, this optical system exhibits a lamp function such as a tail lamp or a stop lamp, and an LED whose emission color is red is used.

  In the optical system shown in FIG. 2B, the emitted light of the LED 7 disposed on the other same side surface 8b side of each prism 3 is introduced into the prism 3 from the side surface 8b toward the opposite side surface 8a. The light is guided through the prism 3 to the other side surface 8a facing, and the light reflected (totally reflected) by the side surface 8a toward the bottom surface 5 is guided through the prism 3 to the bottom surface 5 to reach the bottom surface 5. The optical path emitted from the lamp 5 to the outside of the lamp 10 is formed.

  In this case, the light emitted to the outside of the lamp 10 is irradiated obliquely downward of the vehicle in a state where the lamp 10 is mounted on the vehicle. Therefore, this optical system, for example, exhibits the function of a back lamp or an illumination light source for a vehicle rear monitoring camera. In the case of a backlight, an LED having a white emission color is naturally used. In the case of an illumination light source, not only a white LED but also an infrared LED can be used. When the infrared LED is used, the degree of freedom in light distribution design is increased because the driver of the oncoming vehicle is not hindered.

  The optical system shown in FIG. 2 (c) is different from the optical systems (a) and (b) described above, and light emitted from the outside of the lamp 10 toward the lamp 10 is transmitted from the bottom surface 5 of the prism 3 to one of the prisms 3. Light that is introduced into the prism 3 toward the side surface 8a, guided through the prism 3, reaches one side surface 8a of the prism 3, and is reflected by the side surface 8a toward the other side surface 8b. Light guided to the other side surface 8b, reflected from the side surface 8b and directed toward the bottom surface 5 is guided through the prism 3 to reach the bottom surface 5, and is emitted from the bottom surface 5 to the outside of the lamp 10 again. It has become.

  In this case, the light emitted outside the lamp 10 is emitted toward the light source direction of the light emitted toward the lamp 10 in a state where the lamp is mounted on the vehicle. Therefore, this optical system exhibits a retroreflection function.

  As described above, the prism lens constituting the vehicular LED lamp of the present invention controls the optical path of the light emitted from the LED light source and emits it outside the lamp, and the outside of the lamp into the lamp. Three systems of optical systems are configured, including one system for emitting incident light to the outside of the lamp again.

  Therefore, the vehicle LED lamp according to the present invention can have a plurality of functions including retroreflectors such as a tail lamp, a stop lamp, a back lamp, an illumination light source for a vehicle rear monitoring camera, and the like.

  When the tail lamp and stop lamp are used in common, the switching method is to change the brightness by adjusting the LED drive current, or the apparent brightness felt by humans by adjusting the duty ratio by pulsing the LED. And a method of dividing each lighting area into a tail lamp and a stop lamp.

  In the above embodiment, it has been described that the prism lens is made of a translucent member. However, a half mirror surface can be formed by forming a half mirror film on two side surfaces on which LED light of each prism is incident. . In that case, the reflectance can be increased while maintaining the transparency of the LED light, and in particular, the retroreflectance can be improved.

  Further, as shown in FIG. 3, a metal film 11 such as Al or Ag can be formed on the two side surfaces where the light emitted from the LEDs 7 enters the prisms 3 by a vapor deposition method or a plating method to form a mirror surface. . In this case, the reflectance can be further increased as compared with the case where the prism surface is a half mirror surface, and the reflectance of LED light and the retroreflectance can be improved.

  However, in this case, the range in which each LED light on the side surface 8 of the prism 3 enters the prism 3 is such that the metal film removal unit 12 from which the metal film 11 has been removed so that the LED light can enter the prism 3. In the formed portion, the translucent material forming the prism 3 is exposed.

  Also, as shown in FIG. 4, a recess is provided at the position where each LED 7 of the prism 3 is disposed, and the positional relationship between the prism 3 and the LED 7 is maintained by inserting at least the light emitting portion 13 of the LED 7 into each recess. It is also possible to do.

  Further, the positional relationship in the column direction of the respective LED rows arranged on the two side surfaces of the prism is such that the two LEDs are arranged to face each other across the prism, as shown in FIG. It is conceivable that the LEDs 7 are alternately arranged with the prism 3 interposed therebetween.

  The arrangement method to be selected is determined in consideration of the prism surface processing method, the prism reflection efficiency, the method of holding the LED with respect to the prism, the desired light distribution pattern, and the like.

  The LED rows on both sides of the prism are not necessarily arranged in the same manner. The number of LEDs on each side, the distance between adjacent LEDs, and the like are lamps that use the LED rows as light sources. It is set in consideration of the type of unit, brightness, light distribution characteristics, and the like.

  Furthermore, the LED rows on both sides of the prism need not necessarily use LEDs that emit light of the same color tone, and are set in consideration of the color tone of the light defined in the lamp unit using the LED row as a light source. Is done.

  As described above, the vehicular LED lamp according to the present invention is arranged such that the LED serving as the light source is placed close to or inserted into the lens that controls the light distribution of the light emitted from the LED light source. . Therefore, it is possible to make the lamp thinner, and it is possible to secure a degree of design freedom even when it is stored in a limited space.

  Further, since the traveling direction of the light emitted from the LEDs can be controlled in units of LED groups, it is arranged without providing reflectors provided in each lamp unit or extensions connecting the lamp units as in combination lamps. A plurality of lamp units that require light characteristics or irradiation light with different color tones can be integrally formed. Therefore, a plurality of lamp units can be configured while reducing the thickness of the lamp.

  For example, by arranging a yellow light emitting LED on one side of the prism and an infrared light emitting LED on the other side, the side blinker lamp and the illumination light source for the vehicle side monitoring camera can be integrally configured. In this case, even if infrared light leaks to the front of the vehicle, there is no possibility of hindering the driving of the driver of the oncoming vehicle. Thus, by providing the infrared light emitting LED, it can be used as a vehicle rear monitoring camera illumination light source or a communication medium for inter-vehicle communication.

  Moreover, it can be used not only as a vehicular lamp but also as an illumination light source for a vehicle. For example, the lighting switching between the passenger seat and the driver seat can be performed by individually controlling lighting and lighting of the LED group as one light source module. In addition, the lighting positions of the driver's seat, front passenger seat, rear seat, and the like can be set by adjusting the LED disposition angle with respect to the prism. In particular, it is an effective light source when the lighting position of the rear seat is slightly changed in a one-box car having a wide rear seat.

  The prism surface also serves as a retroreflective surface as well as the reflective surface of the LED light source. Therefore, it is not necessary to provide a retroreflector separately, and restrictions on vehicle design can be reduced and design freedom can be increased.

  In addition, since the LED wiring is configured in LED array units, there is no need for matrix wiring. Therefore, even if one LED is different from the forward voltage of the other LEDs, it hardly affects the brightness variation of the entire lamp directly.

It is a perspective view which shows the principal part of embodiment concerning the LED lamp for vehicles of this invention. It is a fragmentary sectional view which shows the optical system of the principal part of embodiment concerning the LED lamp for vehicles of this invention. It is a fragmentary sectional view which shows the principal part of other embodiment concerning the LED lamp for vehicles of this invention. Similarly, it is a fragmentary sectional view which shows the principal part of other embodiment concerning the LED lamp for vehicles of this invention. It is a partial front which shows arrangement | positioning of the LED light source in each embodiment concerning the LED lamp for vehicles of this invention. It is a connection diagram which shows the connection method of the LED light source of the conventional vehicle LED lamp. It is sectional drawing which shows the LED lamp for vehicles of a prior art example.

Explanation of symbols

1 lens 2 flat surface 3 prism 4 prism lens surface 5 bottom surface 6 apex angle 7 LED
8, 8a, 8b Side surface 9 Housing 10 Lamp 11 Metal film 12 Metal film removal part 13 Light emitting part

Claims (4)

  A vehicular LED lamp in which a plurality of LEDs serving as a light source are arranged in a lamp chamber formed by a lens and a housing, wherein the lamp chamber side of the lens has a plurality of triangles with apex angles directed toward the lamp chamber A prism lens having a sawtooth shape in cross section in which the prisms are formed substantially in parallel is formed, and the plurality of LEDs on the respective side surfaces of the triangular prism sandwiching the triangular prisms has the optical axis of the LEDs as the triangular prism. The LED lamp for vehicles characterized by being arrange | positioned toward.   The LED light reflected on one common side surface of each triangular prism formed on the prism lens and the LED light reflected on the other common side surface of each triangular prism constitute different optical systems, and the external 2. The vehicle LED according to claim 1, wherein light that has entered the lamp from the inside is configured to be a retroreflective optical system that is sequentially reflected on both side surfaces of the triangular prisms and then emitted to the outside of the lamp again. Light fixture.   The half mirror film or the metal film is formed on at least a part of each side surface of each triangular prism formed on the prism lens, according to any one of claims 1 and 2. LED lighting for vehicles.   The LED disposed on one side surface common to each triangular prism formed in the prism lens and the LED disposed on the other side surface common to each triangular prism emit light having different wavelengths. The vehicular LED lamp according to any one of claims 1 to 3, wherein the vehicular LED lamp is emitted.

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