Patent Grant
9885455
This application is based on and claims priority from Japanese Patent Application No. 2015-113231 filed on Jun. 3, 2015, with the Japan Patent Office, the disclosure of which is incorporated herein in its entirety by reference.
The present disclosure relates to a vehicle lamp. In particular, the present disclosure relates to a vehicle lamp used for vehicles such as, for example, cars.
A vehicle lamp conventionally known in the related art includes a substrate mounted with a light emitting diode (LED) thereon as a light source, a heat dissipating plate disposed on a surface of the substrate at a side opposite to the light source mounting surface, and a reflector disposed at the light source mounting surface side of the substrate (see, e.g., Japanese Patent Laid-Open Publication No. 2015-046235).
In the vehicle lamp having the above-described structure, the substrate, the heat dissipating plate, and the reflector are generally fixed to each other by fastening members such as, for example, screws. Through repeated intensive studies on a vehicle lamp, the inventors of the present disclosure have come to recognize that a light quantity of a vehicle lamp may be reduced due to the fastening structure of the substrate, the heat dissipating plate, and the reflector in the conventional vehicle lamp.
The present disclosure has been made in consideration of such a situation, and an object thereof is to provide a technology of increasing a light quantity of a vehicle lamp.
In order to solve the above-described problem, an aspect of the present disclosure provides a vehicle lamp. The vehicle lamp includes a substrate having a light source mounting surface, a heat dissipating member disposed on a surface of the substrate at a side opposite to the light source mounting surface, a reflector disposed at the light source mounting surface side of the substrate to reflect light emitted from a light source mounted on the light source mounting surface, and a fastening member configured to fix the substrate, the heat dissipating member, and the reflector to each other. The reflector includes a boss portion that protrudes toward the heat dissipating member side and includes a fastening hole for the fastening member. The substrate includes a first opening in an area overlapping with the boss portion in the stacking direction of the reflector, the substrate, and the heat dissipating member. The heat dissipating member is in contact with the substrate to be thermally conductive with the substrate and includes a first portion that includes a second opening in an area overlapping with the boss portion in the stacking direction, a second portion that overlaps with the second opening in the stacking direction and is more spaced apart from the reflector than the first portion to include an insertion hole for the fastening member and a fastening seat surface, and a connecting portion that connects the first portion and the second portion to each other. The boss portion passes through the first opening and the second opening and abuts to the second portion such that the fastening hole and the insertion hole overlap with each other in the stacking direction. According to this aspect, a light quantity of a vehicle lamp may be increased.
In the above-described aspect, the heat dissipating member may include a small width portion having a relatively small width and a large width portion having a relatively large width in an area ranging from the end of the connecting portion which is in contact with the first portion to the insertion hole of the second portion. Accordingly, the stress generated by the fastening of the fastening member may be absorbed by the small width portion.
According to the present disclosure, a light quantity of a vehicle lamp may be increased.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
Hereinafter, preferred exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings. Identical or corresponding components, members, and processes in each of the drawings will be denoted by the same symbols, and overlapping descriptions thereof will be appropriately omitted. Further, the exemplary embodiments are not intended to limit the present disclosure thereto, but are merely exemplary. All features described in the exemplary embodiments or combinations thereof may not be essential for the present disclosure. In addition, for example, the terms “first” and “second” used herein or the claims are not intended to refer to any order or importance but are intended to discriminate a component from another component.
A lamp unit 100 as a vehicle lamp according to an exemplary embodiment is mounted in, for example, a headlamp device 10. The headlamp device 10 includes a pair of headlamp units which are disposed at the front left and right sides of a vehicle, respectively. The pair of headlamp units has a substantially identical configuration, except that the structures thereof are bilaterally symmetrical to each other. Thus,
The headlamp device 10 includes a lamp body 11 and a transparent external cover 12 that covers a front opening of the lamp body 11. The lamp body 11 and the external cover 12 form a lamp chamber 13. The lamp unit 100 as a vehicle lamp is accommodated within the lamp chamber 13. The lamp unit 100 is configured to illuminate at least one of, for example, a high beam light distribution pattern and a low beam light distribution pattern.
The lamp unit 100 is supported to the lamp body 11 by a bracket 50. The bracket 50 is formed of, for example, a resin material. A first tilting member 55 and a second tilting member 57 are attached to the bracket 50. The first tilting member 55 includes an aiming screw 55a attached to the lamp body 11, a screw connection unit 55b provided in the bracket 50 of the first tilting member 55, and an adjustment unit 55c disposed outside the lamp body 11. One end side of the aiming screw 55a is inserted into the screw connection unit 55b, and the other end side thereof is connected to the adjustment unit 55c. The second tiling member 57 includes a ball joint 57a attached to the lamp body 11, a socket 57b that holds the ball of the ball joint 57a, and a hole 57c provided in the bracket 50 of the second tilting member 57. The socket 57b is inserted into the hole 57c. In the present exemplary embodiment, the aiming mechanism is connected to the bracket 50. However, the exemplary embodiment is not limited particularly to the configuration. For example, the aiming mechanism may be connected directly to the lamp unit 100 without requiring the brackets 50.
When the aiming screw 55a is rotated through the adjustment unit 55c of the first tiling member 55, the bracket 50 is tilted with respect to the lamp body 11 around the ball of the ball joint 57a of the second tiling member 57 as a fulcrum. In this way, the optical axis of the lamp unit 100 may be adjusted.
The lamp unit 100 includes a substrate 110, a reflector 130, a heat dissipating member 150, and a fastening member 170. The lamp unit 100 of the present exemplary embodiment is a so-called parabola-type lamp unit.
The substrate 110 is a substantially plate shaped member that supports a light source 114. The substrate 110 includes a light source mounting surface 112, and the light source 114 is mounted on the light source mounting surface 112. The light source 114 is, for example, a light emitting diode (LED). In the present exemplary embodiment, the main surface of the substrate 110 which faces vertically downward is the light source mounting surface 112. The light source 114 is mounted on the light source mounting surface 112 such that a light emitting surface thereof faces vertically downward. The light source mounting surface 112 is provided with a wiring pattern (not illustrated) to which the light source 114 is electrically connected. In the present exemplary embodiment, the posture of the lamp unit 100 is set such that the light emitting surface of the light source 114 faces vertically downward. However, the posture of the lamp unit 100 is not limited to this configuration. For example, the posture of the lamp unit 100 may be set such that the normal line of the light emitting surface of the light source 114 is in parallel with the horizontal surface. For example, the lamp unit 100 may take a posture of being rotated 90 degrees around the optical axis from the state illustrated in
In addition, the substrate 100 includes a first opening 116 in an area overlapping with a boss portion 136 to be described later in the stacking direction A of the reflector 130, the substrate 110, and the heat dissipating member 150 (in the direction represented by arrow A in
The reflector 130 is disposed at the light source mounting surface 112 side of the substrate 110. The reflector 130 includes a flat-plate-shaped base portion 132 that abuts to the substrate 110, and a reflecting portion 134 that extends from the end of the base portion 132 at the rear side of the vehicle toward the front side of the vehicle while being curved downward. The base portion 132 includes a light source opening 132a in an area overlapping with the light source 114. The reflecting portion 134 includes a reflecting surface 134a that reflects light emitted from the light source 114 mounted on the light source mounting surface 112 toward the front side of the lamp.
The reflecting surface 134a is formed based on a shape of, for example, a rotating parabolic surface of which the rotating central axis is the optical axis of the reflector 130. The reflector 130 is disposed such that the optical axis thereof extends in the front-and-rear direction of the vehicle. The light source 114 is disposed within the light source opening 132a such that the light emitting surface thereof is substantially opposite to the reflecting surface 134a. The mutual positional relationship between the light source 114 and the reflecting surface 134a is set such that a focal point of the reflecting surface 134a overlaps with the light source 114.
The reflector 130 also includes the boss portion 136. The boss portion 136 is provided on the surface of the base portion 132 which is in contact with the substrate 110 and protrudes toward the heat dissipating member 150 side. The boss portion 136 includes a fastening hole 136a for the fastening member 170. The reflector 130 is formed by performing an aluminum deposition on an area of, for example, a resin-molded substrate which corresponds to at least the reflecting surface 134a.
The heat dissipating member 150 is formed by, for example, an aluminum plate and has a function to dissipate heat generated from the light source 114. By providing the heat dissipating member 150, the dissipation performance of heat from the light source 114 may be improved. The heat dissipating member 150 is disposed on the surface of the substrate 110 at the side opposite to the light source mounting surface 112. The heat dissipating member 150 includes a first portion 152, a second portion 154, and a connecting portion 156.
The first portion 152 has a flat plate shape and is in contact with the substrate 110 to be thermally conductive with the substrate 110. In the present exemplary embodiment, the first portion 152 and the substrate 110 are in contact with each other through a heat transfer sheet 158 which has an insulating property and flexibility or elasticity. The heat transfer sheet 158 is provided in an area overlapping with at least the light source 114 in the stacking direction A. The heat transfer sheet 158 is interposed between the substrate 110 and the first portion 152 so that the heat transfer between the substrate 110 and the heat dissipating member 150 may be more reliably ensured, thereby further improving the dissipation performance of heat from the light source 114. The first portion 152 and the substrate 110 may be in direct contact with each other. Without being limited to the heat transfer sheet 158, a thermal interface material (TIM) such as, for example, a thermal conductive grease or a thermal conductive adhesive may be interposed between the first portion 152 and the substrate 110.
The first portion 152 includes a second opening 152a in an area overlapping with the boss portion 136 in the stacking direction A.
The second portion 154 is disposed in a position overlapping with the second opening 152a in the stacking direction A. The second portion 154 is more spaced apart from the reflector 130 than the first portion 152. The second portion 154 includes an insertion hole 154a for the fastening member 170 and a fastening seat surface 154b disposed around the insertion hole 154a. The second portion 154 extends in parallel with, for example, the first portion 152.
The connecting portion 156 connects the first portion 152 and the second portion 154 to each other. One end side of the connecting portion 156 is connected to the first portion 152. Then, the connecting portion 156 extends vertically upward or in a direction separated from the substrate 110 or the reflector 130 from the first portion 152 such that the other end side of the connecting portion 156 is connected to the second portion 154.
The heat dissipating member 150 includes a small width portion T having a relatively small width and a large width portion W having a relatively large width, in an area ranging from an end 156a of the connecting portion 156 which is in contact with the first portion 152 to the insertion hole 154a of the second portion 154. The width N of the small width portion T is smaller than the width M of the large width portion W, and the width M of the large width portion W is larger than the width N of the small width portion T. The range of the area where the small width portion T and the large width portion W are provided is, for example, from the end 156a to the end of the insertion hole 154 which is closest to the connecting portion 156. In the present exemplary embodiment, the small width portion T is provided in the area ranging from the end 156a of the connecting portion 156 to a midway of the connecting portion 156, and the rest of the connecting portion 156 and the second portion 154 form the large width portion W.
Here, the “width” of the small width portion T and the large width portion W refers to a dimension in a direction orthogonal to the extending direction of the member provided with the small width portion T or the large width portion W. In the present exemplary embodiment, the width of the small width portion T refers to the length of the area of the connecting portion 156 where the small width portion T is provided, in the direction orthogonal to the extending direction of the connecting portion 156. Further, the width of the large width portion W refers to the length of the area 156b in the direction orthogonal to the extending direction of the connecting portion 156, and the length of the second portion 154 in the direction orthogonal to the extending direction of the second portion 154. The extending direction of the connecting portion 156 refers to the direction in which, for example, the end 156a of the connecting portion 156 and the end thereof which is in contact with the second portion 154 are arranged. The extending direction of the second portion 154 refers to the direction in which, for example, the end of the second portion 154 which is in contact with the connecting portion 156 and the insertion hole 154a are arranged.
In other words, the connecting portion 156 has a portion in which the opposite sides of the connecting portion 156 become distant from each other stepwise toward the end side of the connecting portion 156 which is in contact with the second portion 154 from the end 156a side. In the present exemplary embodiment, the opposite sides become distant from each other single-stepwise, but may become distant from each other multi-stepwise. Further, the distance between the opposite sides may increase continuously. Further, the connecting portion 156 may have a portion in which opposite sides of the connecting portion 156 become close to each other stepwise or continuously toward the end side of the connecting portion 156 which is in contact with the second portion 154 from the end 156a side. In this case, the small width portion T is provided in a position spaced apart from the end 156a.
In addition, the area of the cross section of the small width portion T which is orthogonal to the extending direction of the member provided with the small width portion T is smaller than the area of the cross section of the large width portion W which is orthogonal to the extending direction of the member provided with the large width portion W. In addition, for example, the width N of the small width portion T is narrower than the width of the area of the fastening seat surface 1 Mb on which the head of the fastening member 170 contacts. Further, the small width portion T and the large width portion W may adopt various shapes and arrangements as also described in modifications to be described later.
The heat dissipating member 150 may be formed by providing a notch along the shapes of the second portion 154 and the connecting portion 156 at a predetermined position of, for example, an aluminum plate and cutting off the internal portion of the notch. The cut-off portion of the aluminum plate becomes the second portion 154 and the connecting portion 156, and the rest thereof becomes the first portion 152.
The fastening member 170 is configured to fix the substrate 110, the heat dissipating member 150, and the reflector 130 to each other. The fastening member 170 is, for example, a screw. As illustrated in
As a result, as illustrated in
As described above, the lamp unit 100 as the vehicle lamp according to the present exemplary embodiment includes the substrate 110, the reflector 130, the heat dissipating member 150, and the fastening member 170. The reflector 130 includes the boss portion 136 that protrudes toward the heat dissipating member 150 side and has the fastening hole 136a. The substrate 110 includes the first opening 116 through which the boss portion 136 passes. The heat dissipating member 150 includes the first portion 152 that includes the second opening 152a through which the boss portion 136 passes, the second portion 154 that is disposed at the upper side than the first portion to include the insertion hole 154a and the fastening seat surface 154b, and the connecting portion 156 that connects the first portion 152 and the second portion 154 to each other. The boss portion 136 protrudes toward the heat dissipating member 150 side such that the front end thereof abuts to the second portion 154. In this state, the fastening member 170 is inserted into and passes through the insertion hole 154a so that the substrate 110, the reflector 130, and the heat dissipating member 150 are fixed to each other.
In a conventional structure of fixing a substrate, a heat dissipating member, and a reflector to each other by using a fastening member, a boss portion provided in the reflector protrudes toward a reflecting surface side. The boss portion is required to have a predetermined height in order to secure a depth of a fastening hole into which the fastening member is engaged. Hence, in the conventional structure, the boss portion may overlap with a light path of light emitted from a light source, in particular, a light path in which light reflected on the reflecting surface travels toward the front side of the lamp. In this case, the traveling of the light toward the front side of the lamp is disturbed by the boss portion, thereby reducing a light quantity of the vehicle lamp.
The overlapping between the boss portion and the light path of light emitted from the light source may be avoided by spacing the substrate and the reflector apart from each other and disposing the boss portion to protrude toward the substrate side such that the boss portion is accommodated in the space between the substrate and the reflector. However, when the substrate and the reflector are spaced apart from each other, a solid angle of a light flux incident on the reflecting surface of the reflector from a light source is reduced. That is, among light emitted from the light source, a quantity of light that can reach the reflecting surface of the reflector is reduced. As a result, the light quantity of the vehicle lamp is reduced.
In the present exemplary embodiment, the boss portion 136 protrudes toward the substrate 110 side and is inserted into and passes through the first opening 116 of the substrate 110 and the second opening 152a of the heat dissipating member 150. Accordingly, since the space for accommodating the boss portion 136 may not be provided between the substrate 110 and the reflector 130, the substrate 110 and the reflector 130 may be positioned close to each other. Thus, it is possible to avoid that the boss portion 136 and the light path of light emitted from the light source overlap with each other and also avoid that the solid angle of the incident light flux is reduced. As a result, the light quantity of the vehicle lamp may be increased.
In addition, the heat dissipating member 150 includes the small width portion T and the large width portion W in the range from the end 156a of the connecting portion 156 which is in contact with the first portion 152 to the insertion hole 154a of the second portion 154. As the two areas having different widths are provided, the small width portion T having a relatively small width naturally becomes a fragile portion compared to the large width portion W having a relatively large width. Hence, the small width portion T is deformed by the stress generated when the fastening member 170 is fastened. Accordingly, the small width portion T is able to absorb the stress generated when the fastening member 170 is fastened. Further, since the stress may be absorbed by the small width portion T, it is possible to avoid that the substrate 110 is distorted by the stress generated at the time of the fastening thereby causing a positional deviation of the light source 114. As a result, it is possible to suppress the accuracy in the formation of a light distribution pattern by the lamp unit 100 from being deteriorated.
The present disclosure is not limited to the above-described exemplary embodiment. Further modifications (e.g., various design modifications) may be made to the present disclosure based on the knowledge of a person ordinarily skilled in the art. The scope of the present disclosure also includes exemplary embodiments to which the modifications are applied. An exemplary embodiment which is newly made by a combination of the above-described exemplary embodiment and a modification exhibits an effect of each of the exemplary embodiment and the modification to be combined with each other.
In the above-described exemplary embodiment, the small width portion T is provided in a part of the connecting portion 156, and the large width portion W is provided in the remaining part of the connecting portion 156 and the second portion 154. However, the dispositions and the shapes of the small width portion T and the large width portion W are not limited to those described in the above-described exemplary embodiment. For example, the small width portion T may be provided in a part of the area ranging from the end of the second portion 154 which is in contact with the connecting portion 156 to the insertion hole 154a, and the large width portion W may be provided in the rest of the second portion 154 and the connecting portion 156.
In addition, as the dispositions and the shapes of the small width portion T and the large width portion W, for example, Modifications 1 to 4 may be exemplified as described below.
In the above-described exemplary embodiment, an LED is exemplified as the light source 114. However, the light source 114 is not limited to the LED, but may be, for example, a semiconductor laser or a valve lamp. In addition, a parabola-type lamp unit is exemplified as the lamp unit 100. However, the lamp unit 100 may be a projector-type lamp unit or a lamp unit of a polarized electron source (PES) optical system.
From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2015-113231 | Jun 2015 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 8523416 | Ohmi | Sep 2013 | B2 |
| Number | Date | Country |
|---|---|---|
| 2015-046235 | Mar 2015 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20160356447 A1 | Dec 2016 | US |
