Patent ID: 12203628

Throughout the drawings and the detailed description, the same reference numerals refer to the same elements. The drawings may not be to scale, and the relative size, proportions, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience.

DETAILED DESCRIPTION

This description provides a comprehensive understanding of the methods, apparatuses, and/or systems described. Modifications and equivalents of the methods, apparatuses, and/or systems described are apparent to one of ordinary skill in the art. Sequences of operations are exemplary, and may be changed as apparent to one of ordinary skill in the art, except for operations necessarily occurring in a certain order. Descriptions of functions and constructions that are well known to one of ordinary skill in the art may be omitted.

Exemplary embodiments may have different forms, and are not limited to the examples described. However, the examples described are thorough and complete, and convey the full scope of the disclosure to one of ordinary skill in the art.

In this specification, “at least one of A and B” should be understood to mean “only A, only B, or both A and B.”

A luminous emblem11according to one embodiment will be described with reference to the drawings.

As shown inFIG.1, the luminous emblem11is used by being mounted on, for example, a front grille of a vehicle. The luminous emblem11includes a substrate12, a housing13, an outer lens14, and an ornament portion15.

Substrate12

As shown inFIG.1, the substrate12is an insulating glass epoxy substrate or the like on which necessary circuit patterns are formed. The substrate12has a substantially circular shape having a through-hole16at a central portion thereof. The substrate12is fixed to the outer lens14, the housing13, and the like by fixing portions (not shown). At least a mounting surface17of the substrate12is made white to facilitate reflection of light. The light reflectance of the mounting surface17of the substrate12is preferably, for example, greater than or equal to 80%. The white color of the substrate12is preferably achieved by mass coloring, but may be achieved by using a resist or the like.

Multiple light-emitting elements18and circuits (not shown) necessary for controlling the light-emitting elements18are mounted on the mounting surface17, which is one surface of the substrate12. The light-emitting elements18include, for example, light emitting diodes (LEDs) that emit visible light. The light-emitting elements18are arranged at least at positions close to the outer edge of the mounting surface17at intervals in the circumferential direction.

Housing13

As shown inFIGS.1and2, the housing13has a shape of a box with a bottom wall19and a peripheral wall20, and one end of the housing13has an opening. The housing13accommodates the substrate12in a state in which the mounting surface17faces the bottom wall19. The housing13is made of, for example, a polycarbonate (PC) plastic, an acrylonitrile-butadiene-styrene (ABS) copolymer plastic, an acrylonitrile-ethylene-propylene-diene styrene (AES) plastic, an acrylonitrile-styrene-acrylate (ASA) copolymer plastic, or the like.

At least an inner surface of the housing13is made white to facilitate reflection of light. The light reflectance of the inner surface of the housing13is preferably, for example, greater than or equal to 80%. The white color of the housing13is preferably achieved by mass coloring, but may be achieved by painting or the like.

In the housing13, an inner surface19aof the bottom wall19and an inner surface20aof the peripheral wall20are both formed by flat surfaces. A curved surface22is provided between the inner surface19aof the bottom wall19and the inner surface20aof the peripheral wall20in the housing13. The curved surface22faces an outer edge transmissive portion21, which will be discussed below, and has such a radius of curvature that it bulges outward. The curved surface22connects the inner surface19aof the bottom wall19and the inner surface20aof the peripheral wall20to each other. The radius of curvature of the curved surface22in the present embodiment is set in a range of 4 mm to 10 mm. A position on the curved surface22that is at the boundary with the inner surface20aof the peripheral wall20is defined to as a second position B. The second position B is a position on the curved surface22that is farthest from the inner surface19aof the bottom wall19.

The housing13includes protrusions23on the inner surface19aof the bottom wall19at positions corresponding to the light-emitting elements18. The protrusions23protrude toward the light-emitting elements18. Each protrusion23is configured to have, for example, a cone shape in order to reflect the light emitted from the corresponding light-emitting element18so as to diffuse the light to the surroundings. The protrusion23reflects some of the light emitted from the light-emitting element18toward the curved surface22.

A distal end of the protrusion23, that is, a position on the protrusion23farthest from the inner surface19aof the bottom wall19is defined as a first position A. The first position A is located closer to the inner surface19aof the bottom wall19than the second position B in the protruding direction of the protrusion23is to the inner surface19aof the bottom wall19.

Outer Lens14

As shown inFIG.1, the outer lens14is provided on the housing13to close the opening of the housing13. The outer lens14is a transparent member that guides light reflected by the inner surface of the housing13to the ornament portion15. The outer lens14is preferably made of, for example, an acrylic plastic such as polymethyl methacrylate or a transparent plastic such as a polycarbonate (PC) plastic. The outer lens14may contain a diffusing material such as a filler that diffuses light in order to increase the light diffusion properties.

Ornament Portion15

As shown inFIG.1, the ornament portion15is attached to the outer lens14to cover the entire outer lens14from the outside. The ornament portion15includes a central transmissive portion24formed by an opening formed at the center and an outer edge transmissive portion21as an example of a transmissive portion formed by an opening formed in the outer edge portion.

The outer lens14is partially exposed from the central transmissive portion24and the outer edge transmissive portion21in the ornament portion15. The ornament portion15performs a luminous display by using light guided by the outer lens14and transmitted by the central transmissive portion24and the outer edge transmissive portion21.

A region in the ornament portion15other than the central transmissive portion24and the outer edge transmissive portion21is a non-transmissive region, which does not transmit light. The ornament portion15is made of, for example, a polycarbonate (PC) plastic or an acrylonitrile-butadiene-styrene (ABS) copolymer plastic. For example, coating, plating, or the like having a light shielding property is applied to the non-transmissive region of the ornament portion15.

Operation of Luminous Emblem11

As shown inFIGS.1and2, when the luminous emblem11is caused to emit light, first, light is emitted from each light-emitting element18mounted on the mounting surface17of the substrate12in the housing13. Some of the light emitted from each of the light-emitting elements18is reflected one or more times between the inner surface19aof the bottom wall19of the housing13and the mounting surface17of the substrate12and is guided by the outer lens14to cause the central transmissive portion24of the ornament portion15to emit light.

Another part of the light emitted from each light-emitting element18is reflected by the corresponding protrusion23and then reflected by the curved surface22, as indicated by a broken line inFIG.2. At this time, since the first position A on the protrusion23is located closer to the inner surface19aof the bottom wall19than the second position B on the curved surface22is to the inner surface19aof the bottom wall19, a sufficient radius of curvature of the curved surface22is ensured. Particularly, the radius of curvature of the curved surface22of the present embodiment is set in a range of 4 mm to 10 mm. Thus, the light reflected by the curved surface22travels toward the outer edge transmissive portion21while being appropriately diffused, and thus the outer edge transmissive portion21properly emits light.

This configuration improves the light emission efficiency in the outer edge transmissive portion21without using an inner lens like the one disclosed in Japanese Laid-Open Patent Publication No. 2014-141197. Specifically, since it is not necessary to ensure a sufficient space for accommodating an inner lens in the housing13, it is possible to achieve both downsizing of the luminous emblem11and improvement of light emission efficiency in the outer edge transmissive portion21.

If the first position A on the protrusion23is not located closer to the inner surface19aof the bottom wall19than the second position B on the curved surface22is to the inner surface19aof the bottom wall19, a sufficient radius of curvature of the curved surface22cannot be ensured. In this case, the light reflected by the curved surface22would be shifted toward the central transmissive portion24and would not travel toward the outer edge transmissive portion21. As a result, the light guided to the outer edge transmissive portion21would become insufficient, and the light emission efficiency in the outer edge transmissive portion21would decrease.

Advantages of Embodiment

The above-described embodiment achieves the following advantages.

(1) The housing13of the luminous emblem11includes the curved surface22and the protrusions23. The curved surface22is provided between the inner surface19aof the bottom wall19and the inner surface20aof the peripheral wall20, faces the outer edge transmissive portion21, and has a curvature. The protrusions23are provided on the inner surface19aof the bottom wall19at positions facing the light-emitting elements18and reflect some of the light emitted from the light-emitting elements18toward the curved surface22. The first position A, which is a position on each protrusion23which is farthest from the inner surface19aof the bottom wall19, is located closer to the inner surface19aof the bottom wall19than the second position B on the curved surface22, which is a position farthest from the inner surface19aof the bottom wall19, is to the inner surface19aof the bottom wall19.

With the above-described configuration, since the first position A on the protrusion23is located closer to the inner surface19aof the bottom wall19than the second position B on the curved surface22is to the inner surface19aof the bottom wall19, a sufficient radius of curvature of the curved surface22is ensured. Accordingly, some of the light emitted from the light-emitting elements18is reflected by the protrusions23and then reflected by the curved surface22to travel toward the outer edge transmissive portion21while being diffused. This configuration improves the light emission efficiency in the outer edge transmissive portion21without using an inner lens like the one disclosed in Japanese Laid-Open Patent Publication No. 2014-141197. Specifically, since it is not necessary to ensure a sufficient space for accommodating an inner lens in the housing13, it is possible to achieve both downsizing of the luminous emblem11and improvement of light emission efficiency in the outer edge transmissive portion21.

(2) In the luminous emblem11, the radius of curvature of the curved surface22is greater than or equal to 4 mm.

With this configuration, since the radius of curvature of the curved surface22is set to be greater than or equal to 4 mm, the light reflected by the curved surface22is allowed to be guided to the outer edge transmissive portion21while being diffused. This further improves the light emission efficiency in the outer edge transmissive portion21.

(3) In the luminous emblem11, the radius of curvature of the curved surface22is less than or equal to 10 mm.

With this configuration, since the radius of curvature of the curved surface22is set to be less than or equal to 10 mm, excessive diffusion of the light reflected by the curved surface22is suppressed. This maintains the light emission efficiency of the outer edge transmissive portion21in a favorable manner.

Modifications

The above-described embodiment may be modified as follows. The above-described embodiment and the following modifications can be combined as long as the combined modifications remain technically consistent with each other.

As long as the first position A on the protrusion23is located closer to the inner surface19aof the bottom wall19than the second position B on the curved surface22is to the inner surface19aof the bottom wall19, the radius of curvature of the curved surface22may be less than 4 mm.

As long as the first position A on the protrusion23is located closer to the inner surface19aof the bottom wall19than the second position B on the curved surface22is to the inner surface19aof the bottom wall19, the radius of curvature of the curved surface22may be greater than 10 mm.

Various changes in form and details may be made to the examples above without departing from the spirit and scope of the claims and their equivalents. The examples are for the sake of description only, and not for purposes of limitation. Descriptions of features in each example are to be considered as being applicable to similar features or aspects in other examples. Suitable results may be achieved if sequences are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined differently, and/or replaced or supplemented by other components or their equivalents. The scope of the disclosure is not defined by the detailed description, but by the claims and their equivalents. All variations within the scope of the claims and their equivalents are included in the disclosure.